47474.0001.8025180.1

BOISE PAPER HOLDINGS LLC RETIREMENT SAVINGS PLAN

SUMMARY PLAN DESCRIPTION FOR

BARGAINING HOURLY EMPLOYEES AT:

Wallula Paper 651, branches 589 & 593

Effective 10/01/2017 (1st Edition) VERSION 39

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About This Summary This booklet constitutes the Summary Plan Description (SPD) for the Boise Paper Holdings, L.L.C. Retirement Savings Plan. In addition, separate investment fund fact sheets describe in detail the investment choices available in the savings plans and are also a part of the SPD. The SPD also constitutes part of a prospectus covering securities that have been registered under the Securities Act of 1933 (the “Securities Act”). More detailed information about your savings plan can be found in the plan document. If there is a conflict between statements in the SPD and plan document, the terms of the plan document will govern all rights and obligations of participants, beneficiaries, plan fiduciaries, and the company. You can get copies of the official plan document free of charge by contacting: Corporate Secretary Packaging Corporation of America 1955 West Field Court, Lake Forest, IL 60045 Telephone Number: (800) 456-4725 This SPD reflects plan provisions as of October 1, 2017, as they apply to union hourly employees at the Wallula, Washington location. Neither this SPD nor any of the company’s policies or benefit plans should be considered a contract for purposes of employment or payment of compensation or benefits. Employment with Packaging Corporation of America and its subsidiaries, is “at will” and may be terminated at any time, with or without cause, by either the employee or the company, subject to any applicable collective bargaining agreement.

THIS DOCUMENT CONSTITUTES PART OF A PROSPECTUS COVERING SECURITIES THAT HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933

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Important Telephone Numbers and Websites For help and information about the Boise Paper Holdings, L.L.C. Savings Plan: Phone: PCA Benefits Center at 1-877-453-0945

The Interactive Voice Response system is available 24 hours a day, Monday through Saturday and after 1pm Central time on Sunday. PCA Benefits Center representatives are available Monday through Friday from 8am to 5pm Central time to assist you.

Website: Your Benefits Resources™ site (resources.hewitt.com/pca) Address: PCA Benefits Center PO BOX 1479 Lincolnshire IL 60069-1479

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Table of Contents Introduction ............................................................................................................................................................. 3 Eligibility .................................................................................................................................................................. 3 Enrolling in the Plan ................................................................................................................................................ 3 Access to Your Plan Account .................................................................................................................................. 3 Contributions and Contribution Limits ..................................................................................................................... 4

Automatic Escalation Option ............................................................................................................................... 5 Catch-up Contributions ........................................................................................................................................... 5 Rollover Contributions ............................................................................................................................................. 5 Company Contributions........................................................................................................................................... 6 Vesting .................................................................................................................................................................... 7

Breaks in Service ................................................................................................................................................ 7 Investing Your Savings ........................................................................................................................................... 8

Investment Fund Fees ...................................................................................................................................... 10 Changing Your Investment Choices ...................................................................................................................... 11

Multiple Daily Transactions ............................................................................................................................... 11 Potential Delays for Transactions ......................................................................................................................... 11 Employee Stock Ownership Plan .......................................................................................................................... 12

Cash Dividend Election ..................................................................................................................................... 12 Default Dividend Election ............................................................................................................................. 12

Full Vesting of Dividends .................................................................................................................................. 13 Distributions ...................................................................................................................................................... 13 Investments and Transfers ............................................................................................................................... 13 Fiduciary Oversight of the Employee Stock Ownership Plan ............................................................................ 13

Valuation of Your Account ..................................................................................................................................... 13 Statement of Account ....................................................................................................................................... 13

Loans .................................................................................................................................................................... 14 Applying for a Loan ........................................................................................................................................... 14 Loan Payoff ....................................................................................................................................................... 15 Loan Policy ....................................................................................................................................................... 15 Defaulting on a Loan ......................................................................................................................................... 16

Withdrawals .......................................................................................................................................................... 16 General Rules for All Withdrawals .................................................................................................................... 16 Withdrawal Options ........................................................................................................................................... 16

Distributions .......................................................................................................................................................... 17 Account Balances of $1,000 or Less ................................................................................................................ 17 Account Balances of More than $1,000 ............................................................................................................ 17 Total Distributions ............................................................................................................................................. 18 Military Distributions .......................................................................................................................................... 18 Requesting a Distribution .................................................................................................................................. 18

Retirement ............................................................................................................................................................ 18 Required Minimum Distributions ........................................................................................................................... 18

Requesting Periodic Distributions ..................................................................................................................... 19 Taxes and Rollovers ............................................................................................................................................. 19

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Pre-Tax Contributions ....................................................................................................................................... 19 Direct Rollover .................................................................................................................................................. 19 Indirect Rollover ................................................................................................................................................ 19 No Rollover ....................................................................................................................................................... 20 Beneficiaries ..................................................................................................................................................... 20 Roth 401(k) Contributions ................................................................................................................................. 20 Direct Rollover .................................................................................................................................................. 20 60-day Rollover ................................................................................................................................................. 20 No Rollover ....................................................................................................................................................... 21 Beneficiaries ..................................................................................................................................................... 21 For More Information about Taxes.................................................................................................................... 21

Death Benefits ...................................................................................................................................................... 21 Naming a Beneficiary ........................................................................................................................................ 22

Transfers ............................................................................................................................................................... 22 Contributions and Leaves of Absence .................................................................................................................. 22 Address Changes ................................................................................................................................................. 23

If Participants Cannot Be Found ....................................................................................................................... 23 Plan Expenses ...................................................................................................................................................... 23 Qualified Domestic Relations Orders/Assignment of Benefits .............................................................................. 23 Claims and Appeals .............................................................................................................................................. 24

How to Claim Benefits ...................................................................................................................................... 24 In General .................................................................................................................................................... 24 Claim Limitation ............................................................................................................................................ 25

If a Claim Is Denied .......................................................................................................................................... 25 Documents ........................................................................................................................................................ 25 Legal Action ...................................................................................................................................................... 25 Information You Provide ................................................................................................................................... 25

Other Important Information about the Plan .......................................................................................................... 26 Plan Sponsor .................................................................................................................................................... 26 Identification Number ........................................................................................................................................ 26 Plan Name and Number ................................................................................................................................... 26 Plan Amendment Rights ................................................................................................................................... 26 Type of Plan ...................................................................................................................................................... 26 Administration of the Plan ................................................................................................................................. 27

Plan Administrator and Agent for Service of Legal Process .................................................................................. 27 Trustee and Record Keeper of the Plan ........................................................................................................... 28 Plan Year .......................................................................................................................................................... 28 IRS Approval ..................................................................................................................................................... 28

Your Rights under ERISA ..................................................................................................................................... 29 Plan Documents ............................................................................................................................................... 29 Duties of Plan Fiduciaries ................................................................................................................................. 29 Exercising Your ERISA Rights .......................................................................................................................... 29 Assistance with Your ERISA Rights .................................................................................................................. 29 Company Support for Your ERISA Rights ........................................................................................................ 30

Additional Information ........................................................................................................................................... 30

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Introduction This booklet provides an overview of the Boise Paper Holdings, L.L.C. Retirement Savings Plan. Separate investment fund fact sheets provide detailed descriptions of the investment funds available to you in the plans. These materials, along with periodic mailings you receive, are the Summary Plan Description (SPD). This plan is intended to comply with Section 404(c) of the Employee Retirement Income Security Act (ERISA) and the related regulations. This means you are fully responsible for the results of the investment decisions you make in the plan and other plan fiduciaries will not be liable for investment losses that result from your decisions. It is important for you to learn about the plan and make investment decisions that are right for you. Eligibility You are eligible to participate in the plan if you are a nonunion hourly employee at a participating location, and if you are a union hourly employee, you are eligible to participate if your collective bargaining agreement provides for your participation in the plan. If you provide services to PCA as an independent contractor or a consultant, or as an employee of any company other than PCA or a participating subsidiary, you are not eligible to participate in this plan. Enrolling in the Plan You must enroll in the Plan if you want to contribute pre-tax and/or Roth (after-tax) contributions. Soon after your employment date, you will receive an automatic enrollment notice and an enrollment kit from the PCA Benefits Center. This enrollment kit will provide you with information about the investment funds available to you and how to enroll in the Plan. You will be automatically enrolled with a 3% pre-tax contribution unless you contact the PCA Benefits Center to decline enrollment, or enroll with a different contribution amount. Your contributions will be taken as soon as administratively feasible following your employment or your enrollment. Access to Your Plan Account Using your Username and Password, you may access your plan account by: Logging on to the Your Benefits Resources™ site.

The first time you go to the Your Benefits Resources site at http://resources.hewitt.com/pca, enter the last four digits of your Social Security number, your birth date, and your ZIP code. — Note: If you have a 401(k) account balance, you will need to use the personal identification number (PIN) or temporary password that you receive in the mail to access the Your Benefits Resources site for the first time. Already enrolled? After you’ve registered, you’ll just need your user ID and password to log on. You’ll use the same password if you call the PCA Benefits Center.

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Call the PCA Benefits Center at 1-877-453-0945. The Interactive Voice Response system is available 24 hours a day, Monday through Saturday and after 1pm Central time on Sunday. PCA Benefits Center representatives are available Monday through Friday from 8am to 5pm Central time to assist you. You’ll use the same password as you use for the Your Benefits Resources site.

Both the Your Benefits Resources site and the PCA Benefits Center let you: ■ Check your fund balances ■ Change your investment allocation and contribution percentages ■ Request loans ■ Perform other activities related to your account The website also provides information about your plan, interactive calculators, and investment planning tools. The PCA Benefits Center is available 24 hours a day, Monday through Saturday and after 1 pm Central time on Sunday. PCA Benefits Center representatives are available Monday through Friday from 8am to 5pm Central time. Written requests for plan transactions will not be accepted. All transactions must be made through the website or by calling the PCA Benefits Center. If you are no longer employed by PCA but still have funds in the plan, your password allows you to continue to use the website or the PCA Benefits Center. Contributions and Contribution Limits You may contribute from 1% to 50% of your eligible compensation to the plan on a pre-tax basis and/or Roth (after-tax) basis. Eligible compensation generally means your hourly wages. “Pre-tax” means that your savings plans contributions are deducted from your pay before federal and state income taxes are computed and withheld. This allows you to save a portion of your income before the government taxes it. Your contributions are taxed only when they are withdrawn. “Roth” means you put in money after it is taxed. As long as you keep that money in your account for at least five years and do not withdraw it before age 59½, you will not pay any more taxes on those contributions or the earnings on those contributions. This is known as The 5 Year Rule. Regular after-tax contributions are not allowed. You may change the amount you contribute or the election between pre-tax and Roth at any time by accessing your account through the website or by calling the PCA Benefits Center. Changes you make will normally take effect in the first pay period after the date your transaction is communicated to PCA. Federal law limits the maximum amount you can contribute to the plan in a single year. This limit is $18,000 in 2017 and $18,500 in 2018. The amount is indexed annually for inflation. Federal law also limits contributions by “highly compensated employees.” “Highly compensated employees” are employees who earn a defined annual income in a given year, which may be adjusted annually for inflation. If you are highly compensated by this federal definition, your contributions may be limited throughout the year to reflect the maximum contribution rates permitted by law. You will be notified if this limit affects you.

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Federal law also limits total annual contributions to your account. For 2017 this amount is $54,000 and for 2018 this amount is $55,000 (this dollar amount may be adjusted annually). This limit includes the total of your contributions and all company contributions made on your behalf to your plan. You will be notified if this limit affects you. The plan is designed to prevent you from exceeding this limit. However, it may be necessary to return a portion of your contributions to comply with this limit. Contributions for “highly compensated employees” may also be refunded after the end of the year in order to satisfy these requirements. You will be notified if these restrictions apply to you. Automatic Escalation Option You may elect future contribution increases to be automatically taken from your paycheck each year on or about March 1. When you enroll, you specify the percentage increase for contributions. If you have activated the automatic escalation option and request a contribution percentage change, your rate escalation will stop. You will receive a reminder of an upcoming contribution rate increase approximately 30 days in advance of the scheduled increase. Catch-up Contributions If you are at least age 50 by the end of the current calendar year, you may be able to contribute “catch-up” contributions. You are only eligible for these special catch-up contributions if you meet the age requirement and if your contributions (pre-tax and Roth 401(k) combined) for the current year are limited by: ■ The legal limit to pre-tax and Roth 401(k) contributions ($18,000 in 2017 and $18,500 in 2018); or ■ The legal limit to annual contributions ($54,000 in 2017 and $55,000 in 2018); or ■ Contribution limits placed on “highly compensated employees.” In 2017 and 2018, the tax deferral for catch-up contributions is limited to $6,000. The limitation is annually indexed for inflation. If you are eligible, catch-up contributions will automatically begin once your contributions exceed one of the limits listed above, and will continue for the remainder of the plan year or until you reach the catch-up contribution limit, whichever occurs first. Rollover Contributions You may be able to transfer funds from a previous employer's 401(k) or other tax-qualified plan, 403(b) plan, governmental 457 plan, simplified employee pension plan (SEP) or conduit IRA directly into your plan. To do this, you: ■ Must be eligible to receive an eligible rollover distribution from the other plan, ■ Must complete a Rollover Form and have your rollover approved by the Plan Administrator,

and ■ Must be eligible to contribute to this savings plan.

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After-tax contributions (other than Roth 401(k) contributions) are not eligible for rollover into this plan. Rollover funds are invested based on your current investment elections, or, if you have not made an investment election, in the applicable Target Retirement Date Fund. See Investing Your Savings. To process a rollover, the plan must receive both your rollover check and the completed Rollover Form at the same time. Note: IRS rules may limit how much of your distribution from the other plan you may roll over into this savings plan. Rollovers from IRAs are permitted only if the IRA contains only funds rolled over from a previous employer's 401(k) plan and other IRS rules are satisfied. For more information on rollovers, visit the Your Benefits Resources site at http://resources.hewitt.com/pca. Rollover contributions to this plan are subject to the rules governing this plan. Company Contributions Company contributions are made pre-tax and are invested in the same manner you have elected for your own contributions. Company contributions may be made in cash or in PCA common stock, at the company’s option. There are two types of company contributions. Company Base Contributions Each pay period, PCA makes a contribution to your 401(k) account. Effective October 1, 2017 the company contribution is calculated as follows:

If as of December 31 of the current year your age plus your years of service is:

Then you receive a company contribution equal to this amount of your actual weekly pay:

Less than 40 2.5% 40-49 3.5% 50-59 4.5% 60-69 5.5% 70 or more 6.5%

If you are on leave (FMLA, personal leave of absence, Accident & Sickness (A&S) leave, workers’ compensation leave, military leave status, layoff status, or Long Term Disability (LTD) leave), the company contribution will continue for up to one year while you are on leave, and the contribution for each week will be calculated based on your hourly rate of pay multiplied by 40 hours. This contribution is deposited into your account even if you do not contribute to the plan. Please note: Your year-end contribution for 2017 will be deposited into your account in January 2018. This contribution will be for the first 9 months of 2017 and calculated using the prior Company Base Contribution rules.

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Company Matching Contributions Effective October 1, 2017, when you contribute to the plan you are eligible to receive a company matching contribution equal to 100% of your contribution up to the first 3%, plus 50% of your contribution up to the next 2%. This means, if you contribute 5% of your pay, you will receive a company match of 4%. Vesting You always own (are vested in) all the contributions you make to your pre-tax account, Roth 401(k) account, rollover account, and any after-tax account (from a prior plan with OfficeMax Incorporated, Boise Cascade Corporation, or Boise Cascade, L.L.C.). You are also vested in any cash dividends paid on PCA common stock. See Employee Stock Ownership Plan. These funds, including earnings or losses on them, cannot be forfeited. If you receive company contributions, you become fully vested in these contributions and the earnings on those funds (except for cash dividends paid on PCA common stock, which are always fully vested) upon the earliest of the following: ■ Reaching age 65; ■ Becoming totally disabled or upon your death while you are an active employee; ■ Termination of your employment as a result of the sale or permanent closure of your location or division; ■ Death while performing qualified military service; or ■ Reaching three years of service.

Service For purposes of determining vesting, you receive credit for a year of service for each full 12-month period during which you are employed commencing on your hire (or rehire) date. Periods of employment of less than a year will be added together (subject to the break in service rules below), and 12 months of employment (whether or not successive) will equal a year of service. Breaks in Service A break in service occurs when you terminate employment for any reason, when you fail to return from an authorized leave of absence, or when you are absent from service for more than 12 months for a reason other than termination or an authorized leave of absence. However, if you return to work and perform an hour of service within 12 months of your termination (or within 12 months of the date your authorized leave of absence began), you will not have a break in service and you will receive service credit for the period between your termination (or the date your leave of absence began) and the date you returned and performed an hour of service. A break in service that occurs before you are vested in the plan will affect your vesting rights. In such a case, you will forfeit the company's contributions to your account. (There is an

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exception to this for breaks in service resulting from birth or adoption of your child. If this might affect you, you must notify the Plan Administrator within 30 days after the beginning of your maternity or paternity leave.) If you return to work for PCA as an employee before incurring a five-year break in service, the company's contributions to your account prior to the break in service will be restored to your account. Any service credit you had before you left the company will be counted upon your return, and you will then continue to earn service credit. However, if you return to work after a break in service of five years or more, the amount forfeited will not be restored. In this case, any service credit you earned before you left the company is forfeited. Of course, if you are already vested when you leave the company, you will remain vested when you return. Investing Your Savings Following is a brief description of the investment options available to you under the plan. The plan’s investment funds are subject to change. Current and detailed information about the plan’s investment options, and the most recent prospectus on each of the investment options offered under the Plan, may be obtained online at the Your Benefits Resources site at http://resources.hewitt.com/pca or by calling the PCA Benefits Center at 1-877-453-0945. Assets in these investment funds are managed by professional investment managers, except for the Self-Directed Brokerage Account. The PCA Investment Committee monitors the performance of these funds and managers. Fund managers may be changed and investment funds may be added, altered, or removed at any time at the PCA Investment Committee’s discretion. Neither the company nor the PCA Investment Committee recommends any investment option over another. The market price of securities held in the trust fund may go up or down, and there is no guarantee as to how much the investments you elect will be worth at the time your benefit is payable. As with any investment, it is possible that from time to time the value of your account may be less than the total of your own contributions and company contributions made on your behalf. This plan is intended to comply with Section 404(c) of the Employee Retirement Income Security Act (ERISA) and the related regulations. This means you are fully responsible for the results of the investment decisions you make in the plan and other plan fiduciaries will not be liable for investment losses that result from your decisions. It is important for you to learn about the plan and make investment decisions that are right for you. No one at the company is authorized to give you investment advice. You should seek advice from your own financial advisor with respect to your investment elections. The names of the investment funds and brief description are shown below. You should review the investment fund fact sheets for complete details, located on the Your Benefits Resources site at http://resources.hewitt.com/pca. Generally, you may make transfers freely among the plan's investment funds. However, some funds may be subject to short-term trading restrictions. Short-term trading is the buying and selling of funds within a short period of time. Short-term trading impacts the overall pricing and liquidity of the plan’s investment funds, and can lead to a negative impact on long-term fund performance. Current fund restrictions that apply to the funds are indicated below. These trading restrictions do not prevent you from transferring your accumulated investments to another fund; they only limit your ability to re-invest in the same fund after you make the transfer. You can find out more about short term trading restrictions by accessing the Your

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Benefit Resources site at http://resources.hewitt.com/pca, or by calling the PCA Benefits Center at 1-877-453-0945. Target Retirement Date Funds*: These funds are the “qualified default investment fund” in the plan, which means that if you do not make an investment election, your account will automatically be invested in the appropriate Target Retirement Date fund based on your current age. These funds are invested in a diversified portfolio of State Street stock and bond funds. Each fund’s allocation between stock and bond funds becomes more conservative over time as it nears its target retirement date. Once a fund reaches its target retirement date (and most conservative planned allocation), it transfers to the Target Retirement Income Fund. The 2060 Target Retirement Date fund is currently the furthest retirement date and the Target Retirement Income Fund is the closest, for those nearing or in retirement. The details of each Target Retirement Date fund asset allocation can be found in the State Street Target Retirement Date fund fact sheet. JP Morgan Stable Value Fund**: The fund is designed to produce a stable value and predictable return while avoiding negative returns. The fund seeks to provide capital preservation, liquidity, and current income at levels that are typically higher than those provided by money market funds. The Fund is managed by JP Morgan. MetWest Total Return Fund*: The fund seeks to maximize long-term total return. The fund’s investments can include government and corporate debt securities, mortgage- and asset backed securities, money market instruments, and derivatives. The fund is managed by Metropolitan West Asset Management, LLC. Templeton Global Bond R6 Fund*: The fund seeks income, with capital appreciation and growth of income, by investing at least 80% of its net assets in bonds of governments and government agencies located anywhere in the world. The fund is managed by Franklin Templeton Investments. NT Collective S&P 500 Index Fund - DC - Non Lending Tier 3*: The fund seeks to approximate the risk and return characteristics of the Standard & Poor’s 500 Index. The fund is managed by Northern Trust. Loomis Sayles Value N Fund*: The fund seeks stock selection expected to drive long-term excess returns. The fund is managed by Loomis, Sayles & Company, L.P. Fidelity Growth Company Fund***: The fund seeks capital appreciation. Fidelity normally invests the fund’s assets primarily in common stocks of domestic and foreign issuers. The fund is managed by Fidelity Management and Research Company. Northern Trust Collective Extended Equity Market Index Fund - DC - Non Lending Tier 3*: The fund seeks to approximate the risk and return characteristics of the Dow Jones U.S. Completion Total Stock Market Index. The fund is managed by Northern Trust. Victory Integrity Small-Cap Value Fund R6 Fund*: The fund seeks to achieve long-term capital growth by investing in stocks of smaller companies (according to their market capitalization) that the team believes are undervalued, but poised to outperform. The fund is managed by Victory Capital. Dreyfus/The Boston Company Small/Mid Cap Growth Fund*: The fund seeks long-term growth of capital. To pursue this goal, the Fund invests, under normal circumstances, at least 80% of its assets in equity securities of small-cap and mid-cap U.S. companies. The fund is managed by The Dreyfus Corporation and sub-advised by The Boston Company Asset Management, LLC. State Street International Equity Index Fund*: The fund seeks a return that approximates the performance of the Morgan Stanley Capital International (MSCI) Europe, Australasia, Far East

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(EAFE) Index while providing daily liquidity. The fund is managed by State Street Global Advisors. American Funds EuroPacific Growth R6 Fund*: The fund seeks to provide long-term growth of capital by investing in companies based outside the United States. The fund is managed by Capital Research and Management Company. Principal Diversified Real Asset I Fund*: The fund seeks a long-term total return in excess of inflation by allocating its assets among the following general investment categories: inflation-indexed bonds, securities of real estate companies, commodity index-linked notes, fixed-income securities, foreign currency, securities of natural resource companies, master limited partnerships (MLPs), publicly-listed infrastructure companies, floating rate debt, securities of global agriculture companies, and securities of global timber companies. The fund is managed by Principal Management Corporation. Packaging Corporation of America Common Stock Fund*: This fund invests in PCA common stock, which is an individual employer security. When you invest in this fund, you’re purchasing an ownership interest in shares of common stock in PCA. Large fluctuations in value can occur since this option contains only one investment. You will be able to direct the voting of the shares credited to your account. See Employee Stock Ownership Plan for more information about investing in the PCA Common Stock Fund. Self-Directed Brokerage Account (SDBA): The Self-Directed Brokerage Account is a brokerage option that affords you more flexibility in choosing your own retirement savings investments by allowing you to invest in thousands of individual stocks, bonds and mutual funds. The SDBA is held through Alight Financial Solutions (d/b/a Hewitt Financial Services, LLC), a broker-dealer subsidiary of Alight Solutions, member FINRA/SIPC. Additional details on the SDBA offered through HFS are available by contacting an HFS representative at 800-890-3200 between 9:00 a.m. and 7:00 p.m. Eastern Time, Monday through Friday. Please note that additional commissions and fees may apply to brokerage transactions. * If you transfer $5,000 or more out of this fund, then you are blocked from transferring amounts of $5,000 or more back into this fund for 30 calendar days. This restriction will be applied individually to each transfer, not cumulative. This restriction does not apply to distributions or new loans made out of this fund. ** You cannot transfer money directly from the JP Morgan Stable Value Fund into the Self-Directed Brokerage Account. You must first transfer money into another investment option for at least 90 days before it is moved into the Self-Directed Brokerage Account. *** If you transfer out of the Fidelity Company Growth Fund, then you are blocked from transferring any amount back into the fund for 60 calendar days. This restriction does not apply to distributions or new loans made out of this fund. Investment Fund Fees There are investment management fees associated with the plan's investment funds. Most of the plan's investment funds are managed by investment professionals who buy and sell securities and oversee the fund's portfolio of investments. The fees for investment management services are established by each fund company and are paid by participants having a balance in that fund. Investment management fees are referred to as a fund's “expense ratio” and are automatically deducted from the fund's investment return. You can compare the expense ratios among the plan's investment funds by accessing the Your Benefit Resources site at http://resources.hewitt.com/pca, or by calling the PCA Benefits Center at 1-877-453-0945.

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Changing Your Investment Choices You can change where your current contributions are being invested or make fund transfers of any money already in your account at any time, subject to the restrictions described below. Fund transfers are made by electing to move either a percent or dollar amount out of a fund and specifying the percent of the transfer that should move to the new fund(s). You may also elect to make a reallocation transfer where you choose a percentage each fund should hold of your total account balance. From time to time, you may also elect to automatically rebalance your investment funds to your current investment election percentages for new contributions. You may choose to have your investment funds automatically rebalanced: ■ Annually (every 365 days), ■ Semiannually (every 180 days), or ■ Quarterly (every 90 days). If you have elected to use the automatic rebalance feature, you will receive an initial confirmation of your rebalance election and the scheduled dates that the rebalance will occur, and confirmation of future rebalances when they occur. All transactions are made by accessing the Your Benefits Resources site at http://resources.hewitt.com/pca or by calling the PCA Benefits Center. Multiple Daily Transactions If you are making more than one transaction that will involve your funds (e.g., loans, withdrawals, and fund transfers) on a given day, you should discuss with a representative the order in which those transactions will be processed (for example, fund transfers may be processed before withdrawals). Be sure you know which of your transactions involving the transfer of funds will be processed first. The Plan Administrator may establish market-timing restrictions for any fund, including: ■ Requiring that money transferred into any fund remain there for a specified period of time before being transferred out, ■ Not allowing you to transfer money into a fund for a specified period of time once you have

transferred money out of that fund, ■ Establishing a maximum number of trades in and out of a fund during a specified period of

time, and ■ Imposing penalties if you violate the rules that the Plan Administrator has established.

Potential Delays for Transactions The trustee, in its discretion or as directed by the investment managers, may limit the daily volume of its purchases or sales of securities (and hence may limit the plan’s transactions) in any of the investment funds. The trustee also may not be able to complete transactions on a particular day for other reasons, such as a suspension of trading in an asset important to one of

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the investment funds or a major market disruption. For example, the NYSE may halt trading. If trading is halted for a period of time, but the market does not close for the day, the website and PCA Benefits Center will remain open. However, if the market closes early for the day, transactions will not be accepted for processing that day but will instead be accepted for processing the next business day. System limitations or malfunctions, or the volume of web-based or telephone communications, may also cause delays in your ability to request a transaction or the trustee's ability to process a transaction. If the trustee limits the volume of purchases or sales in a security in one of the investment funds or cannot complete certain plan transactions in one of the investment funds on a given day, execution of participant requests related to that particular investment fund may be delayed. You will be informed if, for any reason, a transaction is not completed on the day requested. Once a transaction has been requested, it cannot be revoked after the cut-off time for that day’s requests. If a transaction is not processed on the day requested, the transaction will be completed as soon as administratively possible on the following or subsequent business days. The transaction will be priced according to the unit prices in effect on the day the transaction is completed. Transactions requested in the days following a day the trustee did not complete all previously requested transactions may not be completed on the day requested. All prior days' transactions must be completed first. Employee Stock Ownership Plan The portion of your plan account invested in PCA common stock is part of an Employee Stock Ownership Plan (ESOP). The ESOP portion of the plan is designed to invest primarily in PCA common stock and to meet the applicable requirements for an ESOP as provided under Section 4975(e)(7) of the Code and Section 54.4975-11(a)(2) of Federal Treasury Regulations. Cash Dividend Election Cash dividends paid on PCA common stock are generally used to purchase additional shares of PCA common stock. However, you can elect to have future cash dividends on shares of PCA common stock credited to your ESOP account paid directly to you. To make an election to have future cash dividends paid directly to you, access the Your Benefits Resources site at http://resources.hewitt.com/pca or call the PCA Benefits Center at 1-877-453-0945. To make an election on the website, simply log on to the home page, and click on the prompt entitled Make Your Dividend Payout Choice under the category “Manage.” If you elect to have future cash dividends paid directly to you, your election will remain in effect until you revoke it. Cash dividends will be mailed to the home address on file with the plan record keeper and will be reported as taxable income on Form 1099-R. Cash dividends paid from the plan cannot be rolled over into an IRA or into another 401(k) plan. Default Dividend Election No action is required if you do not want future cash dividend payouts made directly to you. Cash dividend payouts will continue to be reinvested towards the purchase of additional shares of PCA common stock and credited to your ESOP account.

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Full Vesting of Dividends Cash dividends paid on PCA common stock are always 100% vested without regard to whether you are fully vested in the PCA common stock. Distributions Subject to the distribution provisions of the plan, your ESOP account will be distributed in cash, unless you elect to receive a distribution in PCA common stock in accordance with procedures established by the Plan Administrator. Investments and Transfers You may invest none, all, or a portion of your contributions in PCA common stock under the ESOP component of the plan. Company contributions may be made to the ESOP in the form of PCA common stock or may be made in cash. You have the right to transfer amounts invested in PCA common stock into other investments offered by the plan through the Your Benefits Resources site at http://resources.hewitt.com/pca or by calling PCA’s Benefits Center at 1-877-453-0945. Shares of PCA common stock held in the ESOP are subject to short-term trading restrictions. See Changing Your Investment Choices. Fiduciary Oversight of the Employee Stock Ownership Plan PCA currently maintains a Benefits Administration Committee and an Investment Committee (together, the “Committees”) to oversee the administrative and financial aspects of the plan. As part of their oversight authority, the Committees may delegate certain duties and responsibilities to outside parties. The Committees have appointed an independent fiduciary, GreatBanc Trust Company, to assume the fiduciary responsibility for monitoring and overseeing the investment of the PCA common stock in the ESOP component of the plan and to vote any non-voted shares of PCA common stock. GreatBanc Trust Company is a trust company licensed by the State of Illinois and an investment advisor under the Investment Advisers Act of 1940. As such, GreatBanc Trust Company will be able to act as an independent fiduciary for situations requiring an investment decision involving PCA common stock. The contact information for GreatBanc Trust Company is: GreatBanc Trust Company 801 Warrenville Road, Suite 500 Lisle, IL 60532 Valuation of Your Account Your account is valued daily, which means that when you access your account information, the account balance reflected is based on the value of the funds' investments as of the market closing of the immediately preceding business day. Statement of Account You will receive a quarterly Statement of Account showing your contributions and the company's contributions to your account. Your statement will also include your beginning and ending balances in each fund in which you have investments, any gains or losses in your investments, and a record of any withdrawals, loans, distributions, or fund transfers that were processed during the past quarter.

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You can request a statement of your account showing the status of your account including contributions, investment gains or losses, and withdrawals as often as you like by accessing the Your Benefit Resources site at http://resources.hewitt.com/pca or by calling the PCA Benefits Center at 1-877-453-0945. Loans While you are an active PCA employee, you may borrow funds from your account through the loan feature. You repay the loan and interest on the loan balance to your account through automatic after-tax payroll deductions. Loans will be re-amortized if there is a change in your payroll frequency or status. Repayments of loan amounts will be invested in the same investment funds you have chosen for your current contributions. You can have a maximum of two loans outstanding at one time. If you are an active employee with two outstanding loans and you wish to take out a new loan, you must first pay off one of your existing loans. You must wait until the record keeping system reflects the payoff of one of your existing loans before you can request a new loan. The number of loans approved in a 12-month period is limited to two. Other loan terms are: ■ The minimum loan amount is $1,000; the maximum is the least of:

$50,000 reduced by your highest outstanding loan balance during the previous 12 months ending the day before the date the loan is to be made, minus the outstanding loan balance on the date the loan is to be made;

50% of your vested account balance in your pre-tax, rollover, Roth 401(k), and after-tax; or The total market value of your pre-tax account, Roth 401(k) account, after-tax account, and rollover account.

■ The maximum loan repayment period is five years. ■ The interest rate on any new loans is set monthly based on the prime interest rate published

in the Wall Street Journal. Interest on all loans will remain fixed for the term of the loan. Interest paid on a loan is credited to your account. ■ Loans are disbursed proportionately from all investment funds, and the money fund within

the brokerage account. If there are not enough funds in the money fund, Alight Solutions will contact you to redeem some securities to cover the amount of the loan requested. ■ Checks are generally mailed within 3 business days after your loan request. You should allow 7 to 10 days for delivery. The promissory note and Truth in Lending Statement will be mailed under separate cover. ■ Loans are not available to former employees or to active employees whose account has a domestic relations order “hold” placed on it. Applying for a Loan Access your account at the Your Benefits Resources site at http://resources.hewitt.com/pca or call the PCA Benefits Center to request a loan.

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Loan Payoff You may pay off a loan at any time without penalty. To obtain the exact amount of any loan balance to be paid off, you need to call the PCA Benefits Center. Only cashier's checks, certified checks, or money orders made payable to Boise Paper Holdings, L.L.C. Retirement Savings Plan are accepted for loan payoffs. Loan payoffs should be mailed to:

PCA Benefits Center PO Box 1479 Lincolnshire, IL 60069-1479

(For registered or overnight mail) PCA Benefits Center 4 Overlook Pt PO Box 1479 Lincolnshire, IL 60069-1479

Occasionally, because of timing differences, your loan payoff may exceed the amount due on the loan. If this happens, the excess will be refunded to you. If any loan repayments are received from payroll deductions after your loan payoff, they will be refunded to you. Loan Policy If you have an outstanding loan from the plan and go on an unpaid leave of absence, you must continue making loan payments by check or money order. Your check must be for the exact amount of the payment or in a multiple of the payment amount. Partial payments are not allowed. (If you are including additional amounts for missed payments, be sure to indicate this on your check or on an accompanying note.) Your check must be made payable to Boise Paper Holdings, L.L.C. Retirement Savings Plan and your name and employee identification number must be written on the check. If you have an outstanding loan from the plan and take a leave of absence for military service, loan payments may be suspended, although interest will continue to accrue during this period. If the interest rate on the loan is greater than 6%, it will be reduced to 6% during the period of military leave. Upon completion of military service, if the interest rate was reduced, it will return to the original interest rate, and loan payments must resume, with the frequency and amount of loan payments being no less than required under the terms of the original loan. If you terminate employment and have a vested account balance of $1,000 or less, your loan will become a taxable distribution unless you pay it off prior to the automatic distribution of your account. If you terminate employment and have a vested account balance of over $1,000, you must repay the outstanding loan balance in full by the end of the calendar quarter following the quarter in which you terminated. Otherwise, the outstanding loan balance will be made a taxable distribution. Any outstanding loan balance must be paid in full following your death, or it will become a taxable distribution to your beneficiary or estate.

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Defaulting on a Loan If you fail to make a loan payment, your loan will be in default. The remainder of your loan balance will become due, unless you make up the missed payment(s) before the end of the calendar quarter following the calendar quarter in which the required payment(s) was due. For example, if you miss a payment that was due January 10, you have until the end of the next calendar quarter, June 30, to make up the missed loan payment before your entire loan amount becomes due. If you fail to make up the required payment(s), the record keeper will report the amount of the deemed distribution to the IRS. At a minimum, you will be responsible for payment of income tax on the amount of the loan and may be subject to a 10% penalty for taking an early distribution from the plan. Defaulted loan balances and post-default loan interest decrease the loan available amount for future loans. If you have a defaulted loan, you must repay the entire defaulted amount and post-default interest in order to clear the defaulted loan(s). A defaulted loan counts toward the two-loan maximum. Withdrawals There are several withdrawal options available to you with general rules applicable to all. General Rules for All Withdrawals Funds are withdrawn on a pro rata basis across all investment funds and the money fund within the brokerage account (if applicable). Withdrawals cannot be made directly from the Self-Directed Brokerage Account; you will first need to go to the “Brokerage Account” on the website to make sales of securities to place funds into the money fund. It is preferable that you make your own selections of securities to be sold prior to requesting a withdrawal. If you do not place the necessary redemptions to sell your securities and place those proceeds in your money fund, only the amount in the money fund will be available. Withdrawal Options After-Tax (non-Roth) Withdrawals by Employees – If you have an after-tax account other than a Roth account, you can withdraw funds from your after-tax contributions account at any time. When you take a withdrawal, your contributions made before January 1, 1987 (if any) are withdrawn first, and then other after-tax contributions and earnings are taken proportionately. Generally, the taxable portion of your after-tax withdrawal is subject to ordinary income taxes. In addition, if your withdrawal is made prior to age 59½, you may be subject to a 10% penalty tax on the amount of earnings withdrawn. Withdrawals after Age 59½ by Active Employees – At age 59½ or older, you may make withdrawals of your pre-tax, after-tax, rollover, Roth 401(k) and vested company contribution accounts without being subject to the 10% additional tax penalty or the suspension of contributions. Withdrawals are taken pro-rata from all fund sources unless you request otherwise. Taxable amounts withdrawn are subject to ordinary income tax. Rollover Withdrawals by Active Employees – At any time during your employment, you may make withdrawals of your rollover account. Generally, the taxable portion of your after-tax withdrawal is subject to ordinary income taxes. In addition, if your withdrawal is made prior to age 59½, you may be subject to a 10% penalty tax on the amount withdrawn.

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Former Employees – Former employees may make a partial withdrawal of their after-tax, pre-tax, Roth 401(k), rollover, or vested company contribution accounts at any time. Taxable amounts withdrawn are subject to the ordinary income tax. Withdrawals are also subject to the 10% penalty unless:

■ You ended your employment with PCA the year you turned age 55 or older, or ■ You are at least age 59½.

Requesting a Withdrawal To request a withdrawal, call the PCA Benefits Center or visit the Your Benefits Resources site at http://resources.hewitt.com/pca. Generally, withdrawals are processed and a check is mailed to your address on file within 3 business days of your request. You should allow 7 to 10 days for delivery. Distributions When your employment with PCA ends, you are entitled to receive your entire vested savings plan account balance. Participants in the Self-Directed Brokerage Account will need to go to the Your Benefits Resources site at http://resources.hewitt.com/pca to sell securities to place funds into the money fund. It is preferable that you make your own selections of securities to be sold prior to requesting a cash distribution. If the necessary redemptions are not made, Alight Solutions will pay out the amount that is currently in your money fund. They will then liquidate your remaining securities fully and upon settlement of those liquidations, will send you the proceeds. The distribution options available to you depend on the value of your total vested savings plans account balance. See Loans for details on outstanding loan balances at termination or retirement. Account Balances of $1,000 or Less If your vested account balance is $1,000 or less when your employment ends, it will be automatically distributed as soon as possible after your distribution request is processed (but no sooner than 30 days after your employment has ended). If you do not request a distribution, your distribution, less any applicable tax withholdings, will be paid to you automatically within three months following your termination of employment. Account Balances of More than $1,000 If your total vested account balance exceeds $1,000 when your employment ends, you can choose to: ■ Request a distribution of your entire vested savings plan account balance, or ■ Defer distribution of your entire vested savings plan account balance. If you request a distribution, it will be made as soon as possible after receipt of your request (but no sooner than 30 days after your PCA employment has ended). If you defer distribution, you may request partial withdrawals or a total distribution at any future time. However, your entire account must be distributed in a lump sum no later than 60 days following the end of the calendar year in which you reach age 69 or the end of the calendar year

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in which you terminate employment, if later. This rule does not apply if you were age 70½ or older on December 31, 2004 (your birth date was on or before June 30, 1934) or if you were an eligible former employee who had elected prior to January 1, 2005 to take installment payments. In these circumstances, however, required minimum distributions will be required (see Required Minimum Distributions). Total Distributions If you request a total distribution, your account balance will be determined as of the end of the business day your request is processed (generally, the day of the request if the request is received, approved and entered before 3 p.m. Central time on a business day; otherwise, generally the next business day). Your distribution will include your pre-tax, Roth 401(k) and non-Roth after-tax contributions, rollover contributions, vested company contributions, and investment gains or losses as of that date. Shares of PCA common stock in your ESOP account will be paid to you in cash unless you elect a distribution in shares of PCA common stock (see Employee Stock Ownership Plan). Outstanding loan balances will become a taxable distribution to you (see Loans). Your distribution is subject to ordinary income taxes and withholding, and may be subject to penalty taxes. Military Distributions If you are on active qualified military duty for more than 30 days, you are entitled to elect a distribution of all or part of the elective deferral portion of your savings plan account balance as if you had terminated employment. Participants who take a distribution under this provision may not contribute to the plan for a six-month period, beginning on the date of the distribution. Requesting a Distribution To request a distribution, call the PCA Benefits Center or visit the Your Benefits Resources site at http://resources.hewitt.com/pca. Retirement Normal retirement occurs at age 65, but retirement can begin as early as age 55 if you have completed 10 years of vesting service. Required Minimum Distributions If plan rules allow you to remain a participant past April 1 of the calendar year following the calendar year in which you reach age 70½ (see Account Balances of More than $1,000), federal law requires you to take required minimum distributions for the year you turn age 70½ and each year thereafter, unless you are still working for PCA. It is your responsibility to make sure that at least the minimum distribution the law requires for former employees is made to you. Failure to do so may result in severe tax penalties. The required minimum distributions can be based

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on your life expectancy or that of you and your spouse. Speak with a representative through the PCA Benefits Center concerning your required minimum distribution, if applicable. Requesting Periodic Distributions To request periodic distributions, call the PCA Benefits Center. Taxes and Rollovers Withdrawals and distributions may be subject to income tax and tax withholding requirements unless the withdrawal or distribution meets certain requirements explained below. Pre-Tax Contributions Withdrawals and distributions of pre-tax contributions, company contributions, and earnings on these amounts are subject to income tax and tax withholding requirements unless the amount withdrawn is an “eligible rollover distribution” and you elect a “direct rollover.” An eligible rollover distribution is a distribution that can, under the tax laws, be rolled over to an IRA or another employer's plan, deferring taxes on the amount distributed. An eligible rollover distribution may include a withdrawal or distribution of nontaxable after-tax contributions (you previously paid taxes on these amounts before they were contributed to the plan). Eligible employer plans are not required to accept rollovers. If you are considering a rollover, you should discuss this with the other plan’s administrator. A withdrawal or distribution eligible for rollover can be taken in one or a combination of the following ways: (1) paid in a “direct rollover” and/or (2) paid to you. Your choice will affect the income taxes you owe and federal income tax withholding on the withdrawal/distribution. Required minimum distributions and hardship withdrawals are not eligible rollover distributions. You may elect whether or not to have taxes withheld on these distributions by contacting the PCA Benefits Center. Direct Rollover Direct rollovers can be made to a traditional IRA or an eligible employer plan that accepts rollovers. If you choose a direct rollover, your eligible rollover distribution check is made payable to the institution or plan to which you are directing the rollover and mailed to you for delivery to the other institution or plan. You must deposit this check directly to your traditional IRA or eligible employer plan. With the exception of nontaxable after-tax contributions you elect to roll over, these funds will be taxed at the time you withdraw them from your IRA or qualified plan. Indirect Rollover If you choose to have your eligible rollover distribution paid to you, you will receive only 80% of the taxable amount of the eligible rollover distribution plus the amount of the nontaxable after-tax contributions. The plan is required to withhold 20% on the taxable amount and send it to the IRS to be credited against your income taxes (you can choose to have more than 20% withheld). In addition, state taxes are withheld for states that require it. You can roll over the taxable portion of an eligible rollover distribution by contributing it to your traditional IRA or to an eligible employer plan that accepts rollovers within 60 days of receiving it. The amount rolled over will not be taxed until you withdraw it from your IRA or plan. If you want to roll over 100% of the total amount of the taxable distribution to an IRA or an eligible

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employer plan, you must find other money to replace the 20% that was withheld. If you roll over only the 80% that you received, you will also be subject to income tax on the 20% that was not rolled over. After-tax contributions may not be rolled over in an indirect rollover. No Rollover Your distribution (except for distributions of nontaxable after-tax contributions) will be taxed in the current year unless you roll it over. You may be able to apply special tax rules to some lump sum distributions to reduce the tax you owe. However, if you receive the distribution before age 59½, you may also have to pay an additional 10% penalty tax unless your employment ended the year you were age 55 or older or unless the distribution meets other conditions. For more information on this tax, see IRS Form 5329. Beneficiaries If you are a surviving spouse or an alternate payee under a qualified domestic relations order, you generally have the same rollover options described above. If you are a designated non-spouse beneficiary, you are eligible for a direct rollover to a traditional IRA that indicates both the deceased individual and the beneficiary. Other beneficiaries, such as estate or trustee representatives, cannot choose direct or indirect rollovers. Distributions to beneficiaries generally are not subject to the 10% penalty tax and may be subject to special tax rules that reduce the tax owed. Roth 401(k) Contributions This section describes the rollover rules that apply to payments from the plan that are from a designated Roth account. If you also receive a payment from the plan that is not from a designated Roth account, the Plan Administrator will tell you the amount that is being paid from each account. Refer to Pre-Tax Contributions for rules regarding payments that are not from a designated Roth account. Withdrawals of contributions made to a designated Roth account are not taxed. The earnings on those contributions are not taxed as long as either the withdrawal is a qualified distribution or you do a rollover. A qualified distribution is a payment made after you are age 59½ (or after your death or disability) and after you have had a designated Roth account for at least 5 years. In applying the 5-year rule, you count from January 1 of the year your first contribution was made to the designated Roth account. However, if you made a direct rollover to a designated Roth account in the plan from a designated Roth account in another employer plan, your participation will count from January 1 of the year your first contribution was made to the designated Roth account in the other employer plan. Direct Rollover Direct rollovers can be made to a Roth IRA or an eligible employer plan that accepts rollovers from Roth 401(k) accounts. If you choose a direct rollover, your eligible rollover distribution check is made payable to the IRA or employer plan to which you are directing the rollover and mailed to you for delivery to the other institution or plan. You must deposit this check directly to your Roth IRA or eligible employer plan. 60-day Rollover If you do not make a direct rollover, you may still do a rollover by making a deposit within 60 days into a Roth IRA, whether the payment is a qualified or nonqualified distribution. In addition, you can do a rollover by making a deposit within 60 days into a designated Roth account in an employer plan if the payment is a nonqualified distribution and the rollover does not exceed the amount of the earnings in the payment. You cannot do a 60-day rollover to an

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employer plan of any part of a qualified distribution. If you receive a distribution that is a nonqualified distribution and you do not roll over an amount at least equal to the earnings allocable to the distribution, you will be taxed on the amount of those earnings not rolled over, including the 10% additional income tax on early distributions if you are under age 59½ (unless an exception applies). If you do a direct rollover of only a portion of the amount paid from the plan and a portion is paid to you, each of the payments will include an allocable portion of the earnings in your designated Roth account. If you do not do a direct rollover and the payment is not a qualified distribution, the plan is required to withhold 20% of the earnings for federal income taxes (up to the amount of cash and property received other than employer stock). This means that, in order to roll over the entire payment in a 60-day rollover to a Roth IRA, you must use other funds to make up for the 20% withheld. No Rollover If a payment is not a qualified distribution and you are under age 59½, you will have to pay the 10% additional income tax on early distributions with respect to the earnings allocated to the payment that you do not roll over (including amounts withheld for income tax), unless one of the exceptions listed below applies. This tax is in addition to the regular income tax on the earnings not rolled over. Beneficiaries If you are a surviving spouse or an alternate payee under a qualified domestic relations order, you generally have the same rollover options described above. If you are a designated non-spouse beneficiary, you are eligible for a direct rollover to a Roth IRA that indicates both the deceased individual and the beneficiary. Other beneficiaries, such as estate or trustee representatives, only have the direct rollover option to an inherited Roth IRA. Payments from the inherited Roth IRA, even if made in a nonqualified distribution, will not be subject to the 10% additional income tax on early distributions. You will have to receive required minimum distributions from the inherited Roth IRA. For More Information about Taxes This is only a summary of tax and rollover information to you as required by federal law. For more information please refer to the “Special Tax Notice” available on the Your Benefits Resources site at http://resources.hewitt.com/pca. This notice includes additional details about direct rollovers, amounts paid directly to you, the additional 10% penalty tax, special tax treatments, and general information for surviving spouses, alternate payees, and other beneficiaries. You may also obtain a free copy of this notice upon request by calling the PCA Benefits Center at 877 453 0945. The Internal Revenue Code has many complex rules relating to withdrawals and distributions from your savings plans. You should consult a tax advisor before deciding how to handle any distribution or withdrawal. Death Benefits If you die while participating in the plan, your account may be paid to your beneficiary. If your spouse is your beneficiary, he or she may choose to keep funds in the plan if your account

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balance is greater than $1,000 when the plan record keeper is notified of your death. Payments to non-spouse beneficiaries will be in a lump sum. Naming a Beneficiary If you are not married, you may name anyone as your savings beneficiary and change your beneficiary as often as you wish by electing a beneficiary on the Your Benefits Resources site at http://resources.hewitt.com/pca. If you are married and you want to designate a beneficiary other than your spouse, your spouse must provide written consent to the selection of any other beneficiary. The beneficiary designation may not be changed in the future without obtaining your spouse's consent again. The written consent of your spouse must be notarized and filed with Alight Solutions before your death. If you are married at the time of your death and have elected a beneficiary other than your spouse without having received the consent of your spouse, by law, any benefits will be paid to your surviving spouse. If you do not designate a beneficiary or if your beneficiary dies before receiving a complete distribution, the plan pays remaining benefits to your surviving spouse or if none, your estate. Special rules apply to the designation of a trust as beneficiary. If you intend to do this, you should consult with your tax/estate-planning advisor and review your plan provisions carefully. Transfers If your employment classification changes to a group that is not eligible to participate in this plan, your right to continue in the plan as an active contributor ends. Your contributions must end; however, you can keep your funds in the plan and retain all other participant rights. For example, you may make fund transfers or take withdrawals or loans. When you leave the company, your total years of service, including the period of employment when you may not have been eligible to make contributions to this plan, will be counted toward vesting. Contributions and Leaves of Absence When you are on a paid leave of absence, plan contributions and plan responsibilities and rights will automatically continue. If you are on an unpaid leave, all contributions will stop, but your other responsibilities and rights as a participant will continue (including your responsibility to make payments on any outstanding loans). The plan protects rights you may have as an employee under the Family and Medical Leave Act and Pregnancy Disability Act. If you are on a long-term military leave of absence, service in the uniformed services is deemed to be service with PCA. If you are reemployed by the company within the time limits prescribed by law, you are entitled to accrue benefits under the plan as long as you make the necessary employee contributions. Your contributions may not exceed the amount you would have been permitted to make if you had remained employed by the company during your leave. You must make these contributions to the plan during the period beginning with your date of reemployment and not exceeding three times the length of your period of service in the

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uniformed services or five years, whichever is less. For more information about this provision, call the PCA Benefits Center. Address Changes If your address changes, please notify the PCA Benefits Center at 877 453 0945. If Participants Cannot Be Found If the Plan Administrator is unable to find a participant or beneficiary to whom a distribution is due under the savings plan, the participant's account balance will be treated as a forfeiture under the plan. The participant or beneficiary will cease to have an account balance in the plan. If a former participant or beneficiary is located, the plan record keeper will provide the dollar amount of the account and the participant’s or beneficiary’s account will be restored. Plan Expenses As a participant in the plan, you pay a portion of the plan’s administrative expenses. An annual plan administrative expense applies per participant and will be deducted on a quarterly basis from each participant’s account balance. The dollar amount of the expense can be found by logging on to the Your Benefit Resources site at http://resources.hewitt.com/pca and on participant statements. Plan administrative expenses typically include items such as recordkeeping, participant website access, participant statements, plan compliance services, legal and audit plan services. The plan provides that the expenses of operation and administration of the plan, including compensation of the trustee, investment managers, financial advisors, auditors, and administrative service providers and communications will be paid out of the assets of the plan to the extent permitted by law. Brokerage commissions and related expenses are paid out of the assets of the investment fund to which they relate unless stated otherwise. Certain fees, such as fees related to QDRO determination may be allocated to the account of the participant making the request. A communication regarding plan fees and expenses will be provided to participants at least annually. This notice will include general information about fees, a description of fees for participant-level services (such as QDRO determinations), and an explanation of the fees for each investment fund within the plan. In addition, quarterly statements will contain itemized statements of fees and expenses withdrawn from a participant’s account. Qualified Domestic Relations Orders/Assignment of Benefits Normally, your benefits under the plan cannot be assigned to someone else. Your account balance in the plan is not subject to legal judgments, garnishment, liens, or attachment, other than federal tax liens. However, under federal law, the plan is required to comply with a Qualified Domestic Relations Order (QDRO), which is a court order requiring plan benefits to be paid to another person for child support, alimony, or division of property rights in a divorce in

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accordance with state domestic relations laws. A QDRO must satisfy requirements of both state and federal law and may not provide for payments in a manner not permitted by the plan. An administrative fee will be charged to your account for processing a QDRO. If you have questions about QDROs, including the amount of the fee, or if you would like to receive a free copy of the plan’s QDRO procedures, please contact the PCA Benefits Center at 877 453 0945. All correspondence regarding QDROs and your savings plan account must be sent to:

PCA QDRO Team 4 Overlook Pt PO Box 1479 Lincolnshire IL 60069-1479

Claims and Appeals Regulations under the Employee Retirement Income Security Act of 1974 (ERISA) govern claims and appeals regarding your benefits. How to Claim Benefits In General To apply for savings plan benefits, you or your beneficiary should contact the PCA Benefits Center at 877 453 0945. If you have requested a savings plan distribution and your request has been denied, you may file a claim for benefits with the Plan Administrator. You must submit your claim in writing within 60 days of the date of the denial to:

Executive Director - Benefits Packaging Corporation of America 1955 West Field Court Lake Forest, IL 60045

Your claim must include: ■ Your (participant’s) name; ■ Your (participant’s) Social Security number or employee ID number; ■ A statement indicating whether the claim is for a participant or beneficiary; ■ The reason the claim is being filed; ■ A statement of all facts and copies of all documents, materials, or other evidence that you believe relevant to the claim; and ■ A reference to the plan provision(s) on which the claim is based. The Plan Administrator will review your claim according to the terms and conditions of the plan and respond in writing within 90 days after receiving the claim. The Plan Administrator may extend this 90-day period for an additional 90 days for special circumstances by notifying you in writing before the end of the original 90-day period. Whether benefits are due or owed under the plans is determined solely by the Plan Administrator. If your claim is denied, you will receive a written notice of denial, which will:

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■ State the specific reasons for the denial; ■ Refer to the provision(s) of the plan on which the denial is based; ■ Describe any additional material or information necessary for you to perfect the claim and explain why the information is necessary; ■ Explain how you may submit the claim for review and state applicable time limits; and ■ Explain your right to bring a civil action under Section 502(a) of ERISA. The Plan Administrator’s decision shall be final and binding on all parties unless you appeal within the time limits explained below. Claim Limitation In no event may any claim be made more than 180 days after the facts and circumstances giving rise to the claim occurred. If a Claim Is Denied If your claim for a savings plan benefit is denied, you may file a written request for review with the Benefits Administration Committee within 60 days after receiving the Plan Administrator’s notice of denial. You must send your request for review, together with a written statement of your position and any other comments, documents, records, or information that you believe relevant to the claim, to the Benefits Administration Committee at the address indicated below. The Benefits Administration Committee will notify you in writing of its decision within 60 days after receiving your request for review. This 60-day period may be extended an additional 60 days if special circumstances warrant the extension and if you are notified in writing before the original 60-day period ends. The Benefit Administration Committee's written decision will be final and binding on all parties and shall state the facts and specific reasons for the decision and refer to the plan provisions on which the decision is based.

PCA Benefits Administration Committee c/o Executive Director - Benefits Packaging Corporation of America 1955 West Field Court Lake Forest, IL 60045

Documents Upon written request and at no charge, you are entitled to copies of all documents, records, and other information relevant to your claim for benefits. Legal Action You may not file a lawsuit or legal action regarding benefits under the savings plan, unless you first follow the claims and appeals process described above. Information You Provide It is your responsibility to provide accurate and truthful information when you submit your application. If the information is incorrect, PCA and Alight Solutions cannot be held responsible for inaccuracies or any consequences resulting from the provision of incorrect information.

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Other Important Information about the Plan Plan Sponsor Company (Plan Sponsor) Name and Address:

Packaging Corporation of America 1955 West Field Court Lake Forest, IL 60045 Attn: Executive Director – Benefits

If you have a question about a specific benefit provision, please contact the PCA Benefits Center. Your supervisors or other local management of PCA are not authorized to interpret provisions of the plan or make representations that are contrary to the provisions of the plan documents. Identification Number Packaging Corporation of America's Employer Identification Number is 36-2477050. Plan Name and Number Boise Paper Holdings, L.L.C Retirement Savings Plan: ■ Plan Number 002 The Pension Benefit Guaranty Corporation does not guarantee benefits under this plan. Plan Amendment Rights While PCA intends to continue this plan indefinitely, the company reserves the right to amend, modify, or terminate the plan at any time, for any reason at its sole discretion, and to implement any changes required by federal, state, or local law. If a plan is amended or terminated, participants will be notified. The PCA Benefits Administration Committee has authority to adopt plan amendments or to act to terminate a plan. Upon termination of a plan, the accounts of all participants will become fully vested. After payment of investment and plan expenses and previously approved distributions and withdrawals, any remaining plan assets will be distributed among the participants. Plan amendments may not reduce the right of any participant to his or her vested benefit. Type of Plan The plan described in this booklet is a defined contribution plan containing a “cash or deferred arrangement” under Internal Revenue Code Section 401(k) and is intended to be a “qualified” plan under Internal Revenue Code rules. It is also intended to be an “individual account plan” as described in ERISA Section 404(c) and Department of Labor Regulations Section 2550.404c-1. The ESOP portion of the Plan is designed to invest primarily in PCA common stock and to meet the applicable requirements for an ESOP as provided under Section 4975(e)(7) of the Code and Section 54.4975-11(a)(2) of Federal Treasury Regulations.

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Administration of the Plan The PCA Benefits Administration Committee, appointed by the Board of Directors of PCA, is the “named fiduciary” of the plans. The Benefits Administration Committee is responsible for oversight of the operation and administration of the plan. The Benefits Administration Committee has appointed the Executive Director – Benefits as the Plan Administrator. The Plan Administrator is responsible for oversight of the day-to-day administrative operations of the plans. The Plan Administrator is also responsible for ensuring that accurate employee contribution and service records are maintained and that all reports and disclosures required by law are made, as well as authorizing payment of benefits. The Plan Administrator is also responsible for interpreting and administering the plans and has discretionary authority to make all decisions and interpret all plan provisions regarding timing, form, amount and recipients of any payments to be made, and any other matters regarding the plans. The Plan Administrator's interpretation and decisions will be binding on all persons for all purposes, except as otherwise provided under Claims and Appeals. Many of the day-to-day operations of the plans have been delegated to Alight Solutions, including certain record keeping and participant service responsibilities. The PCA Investment Committee, also appointed by the Board of Directors, is responsible for establishing and determining the investment policy and objectives, as well as the number and types of investment funds for the plan. The Investment Committee is also responsible for reviewing the performance of the investment funds and appointing or removing the investment managers for the funds. As part of their oversight authority, the Committees have appointed an independent fiduciary, Great Banc Trust Company, to assume the fiduciary responsibility for monitoring and overseeing the investment of the PCA common stock in the ESOP component of the plan and to vote any non-voted shares of PCA common stock. Great Banc Trust Company may be contacted at: Great Banc Trust Company 801 Warrenville Road, Suite 500 Lisle, IL 60532 Plan Administrator and Agent for Service of Legal Process The Plan Administrator is the designated agent for service of legal process concerning the plans. The Plan Administrator may be contacted by writing:

Executive Director - Benefits Packaging Corporation of America 1955 West Field Court Lake Forest, IL 60045

or by calling 847-482-3000 (not a toll-free number) The PCA Benefits Administration Committee is the plan's agent for service of legal process. The Committee may be contacted by writing:

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Benefits Administration Committee c/o Executive Director - Benefits Packaging Corporation of America 1955 West Field Court Lake Forest, IL 60045 or by calling 847-482-3000 (not a toll-free number).

Legal process may also be served upon the plan trustee identified below. Trustee and Record Keeper of the Plan All assets of the plan are held in trust for the exclusive benefit of participants and beneficiaries. The trustee receives all contributions, invests the amounts contributed, and makes payments as directed by the Plan Administrator. PCA’s Board of Directors has appointed The Northern Trust Company as trustee. The trustee’s address is as follows:

The Northern Trust Company 50 South LaSalle Street Chicago, IL 60675

The PCA Benefits Administration Committee has appointed Alight Solutions as the recordkeeper and third party administrator for the plan. The contact information for Alight Solutions is as follows:

Alight Solutions PO Box 1479 Lincolnshire IL 60069-1479

(For registered or overnight mail) Alight Solutions 4 Overlook Pt PO Box 1479 Lincolnshire IL 60069-1479

Plan Year The financial records of the plan are maintained on a January 1 – December 31 calendar year basis. IRS Approval The plan has received a determination letter from the IRS stating that it meets the requirements for qualification under Section 401(a) of the Internal Revenue Code. The company intends the plan to meet the operational requirements for qualification under Section 401(a) as well. Meeting the requirements for qualification means the plan and related trust are exempt from federal income taxation.

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Your Rights under ERISA As a participant in a savings plan, you have certain rights and protection under the Employee Retirement Income Security Act of 1974 (ERISA). Plan Documents You are entitled to: ■ Examine, without charge, at the Plan Administrator's office and at other specified locations during normal business hours (1) all documents governing the plan, which may include

insurance contracts, trust agreements, and plan descriptions, and (2) a copy of the latest annual report (Form 5500 series) filed by the plan with the U.S. Department of Labor and available at the Public Disclosure Room of the Employee Benefits Security Administration;

■ Obtain, upon written request to the Plan Administrator and for a charge of 25 cents per page, copies of plan documents and other documents governing the operation of the plan, and copies of the latest annual report and summary plan description; and

■ Receive a copy of the plan’s annual financial report each year, which explains the financial status of the plan.

Duties of Plan Fiduciaries In addition to creating rights for plan participants, ERISA imposes duties upon the people who are responsible for the operation of the employee benefit plan. The people who operate your plan, called “fiduciaries” of the plan, have a duty to do so prudently and in the interest of you and other plan participants and beneficiaries. Exercising Your ERISA Rights No one, including your employer, your union (if applicable), or any other person may fire you or otherwise discriminate against you in any way to prevent you from obtaining a benefit under the plan or exercising your rights under ERISA. If your claim for a benefit under the plan is denied or ignored, in whole or in part, you have a right to know why this was done, to obtain copies of documents relating to the decision without charge, and to appeal any denial, all within certain time frames. For a specific description of the claim and appeal procedures and applicable time frames, please see Claims and Appeals. Assistance with Your ERISA Rights Under ERISA, there are steps you can take to enforce your rights. If you believe you have been discriminated against for asserting your rights, you may seek assistance from the U.S. Department of Labor. You may also file suit in federal court if: ■ The Department of Labor is unable to assist you to your satisfaction; ■ You request a copy of plan documents or the latest annual report from the plan and you do not receive it within 30 days (in which case the court may require the Plan Administrator to

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provide the materials and pay you up to $110 a day until you receive the materials, unless the materials were not sent because of reasons beyond the Administrator’s control); ■ You disagree with the final decision on your claim; or ■ You disagree with the plan’s decision or lack of decision concerning the qualified status of a

domestic relations order. In case of court action, the court will decide who should pay court costs and legal fees. If you are successful, the court may order the person you have sued to pay these costs and fees. If you lose, the court may order you to pay these costs and fees, for example, if it finds your claim is frivolous. Company Support for Your ERISA Rights PCA supports both the letter and the spirit of ERISA objectives and requirements. The company is committed to assuring proper treatment of all plan participants and full disclosure of all pertinent information. If you have any questions about the plans or if you have not received the information you have requested, contact the Plan Administrator. If you have any questions about this statement or about your rights under ERISA, or if you need assistance in obtaining documents form the Plan Administrator, you should contact the nearest area office of the Employee Benefits Security Administration, U.S. Department of Labor, listed in your telephone directory, or the Division of Technical Assistance and Inquiries, Employee Benefits Security Administration, U.S. Department of Labor, 200 Constitution Avenue, NW, Washington, DC 20210. You may also obtain certain publications about your rights and responsibilities under ERISA by calling the publications hotline of the Employee Benefits Security Administration. Additional Information If you have questions that this booklet does not answer or explain, contact the PCA Benefits Center at 1-877-453-0945. The Interactive Voice Response system is available 24 hours a day, Monday through Saturday and after 1pm Central time on Sunday. PCA Benefits Center representatives are available Monday through Friday from 8am to 5pm Central time to assist you. You may also make written requests to the Plan Administrator for information or explanations relating to the plan.

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