William Blair Investor Presentation | June 2017

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Confidential: Not for distribution or publication

Disclaimer

Forward-Looking Statements

This presentation contains “forward-looking statements” within the meaning of the Federal Private Securities Litigation Reform Act of 1995. Some of the forward-looking statements can

be identified by the use of terms such as “may,” “intend,” “might,” “will,” “should,” “could,” “would,” “expect,” “believe,” “estimate,” “anticipate,” “predict,” “project,” “potential,” or the

negative of these terms, and similar expressions. You should be aware that these forward-looking statements are subject to risks and uncertainties that are beyond our control. Further,

any forward-looking statement speaks only as of the date on which it is made, and we undertake no obligation to update any forward-looking statement to reflect events or

circumstances after the date on which it is made or to reflect the occurrence of anticipated or unanticipated events or circumstances. New factors emerge from time to time that may

cause our business not to develop as we expect, and it is not possible for us to predict all of them. Factors that may cause actual results to differ materially from those expressed or

implied by the forward-looking statements include, but are not limited to, the following: cyclicality in residential and commercial construction markets; general economic and financial

conditions; weather conditions, seasonality and availability of water to end-users; laws and government regulations applicable to our business that could negatively impact demand for

our products; public perceptions that our products and services are not environmentally friendly; competitive industry pressures; product shortages and the loss of key suppliers; product

price fluctuations; inventory management risks; ability to implement our business strategies and achieve our growth objectives; acquisition and integration risks; increased operating

costs; and other risks, as indicated in our Annual Report on Form 10-K and our Registration Statement on Form S-1 filed with the U.S. Securities and Exchange Commission

(Registration No. 333-217327).

Included in this presentation are estimated results for Q1 2017, which are preliminary, unaudited and subject to completion, reflect management’s current views and may change as a

result of management’s review of results and other factors, including a wide variety of significant business, economic and competitive risks and uncertainties. Such estimated preliminary

results are not guarantees of future performance or outcomes and that actual results may differ materially from the estimated preliminary results.

Non-GAAP Financial Information

This presentation includes certain financial information, not prepared in accordance with U.S. GAAP. Because not all companies calculate non-GAAP financial information identically (or

at all), the presentations herein may not be comparable to other similarly titled measures used by other companies. Further, these measures should not be considered substitutes for the

information contained in the historical financial information of the Company prepared in accordance with U.S. GAAP that is set forth herein.

We present Adjusted EBITDA in order to evaluate the operating performance and efficiency of our business. Adjusted EBITDA represents EBITDA as further adjusted for items

permitted under the covenants of our credit facilities. EBITDA represents our net income (loss) plus the sum of income tax (benefit), depreciation and amortization and interest expense,

net of interest income. Adjusted EBITDA is further adjusted for stock-based compensation, advisory fees, loss (gain) on sale of assets and rebranding, acquisitions and other

adjustments.

Adjusted EBITDA does not include pre-acquisition Adjusted EBITDA. Adjusted EBITDA is not a measure of our liquidity or financial performance under GAAP and should not be

considered as an alternative to net income, operating income or any other performance measures derived in accordance with GAAP, or as an alternative to cash flow from operating

activities as a measure of our liquidity. The use of Adjusted EBITDA instead of net income has limitations as an analytical tool. Because not all companies use identical calculations, our

presentation of Adjusted EBITDA may not be comparable to other similarly titled measures of other companies, limiting its usefulness as a comparative measure. Net debt is calculated

as long-term debt plus capital leases, net of cash and cash equivalents. Free cash flow is defined as cash flow from operating activities less capital expenditures. See the Appendix for a

reconciliation of Adjusted EBITDA to net income (loss) and a reconciliation of free cash flow to cash flow from operating activities.

We present organic daily sales as we believe organic sales growth and organic daily sales growth are useful measures for evaluation our performance as we may choose to open or

close branches in any given market depending upon the needs of our customers or our strategic growth opportunities. See the Appendix for a reconciliation of organic sales and organic

daily sales to net sales.

The Company’s fiscal year is a 52- or 53-week period ending on the Sunday nearest to December 31. The year ended January 1, 2017 includes 52 weeks. The year ended January 3,

2016 includes 53 weeks. The year ended December 28, 2014 includes 52 weeks. Unless the context otherwise indicates, references to years herein refer to our fiscal years.

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Confidential: Not for distribution or publication

Today’s presenters

Doug Black

CEO & Director

Joined SiteOne in April 2014

Previously spent 18 years at CRH plc most recently as President and COO of Oldcastle Inc.

Held a variety of roles including CEO and COO of Oldcastle Materials

Previously a consultant with McKinsey

M.B.A. from Duke and B.S. from the U.S. Military Academy at West Point

Pascal Convers

EVP of Strategy,

Development &

Investor Relations

Joined SiteOne in July 2014

10 years at CRH plc, recently as SVP of Strategy and Development for Oldcastle Materials

Previously CRH’s Managing Director for concrete and landscaping operations in France

Spent 13 years at Eastman Chemical Company, held senior leadership roles in Europe, North America

and Asia-Pacific

M.B.A. from Duke, M.S. from Ecole Des Mines de Paris and B.S. in Chemical Engineering from Rennes

Section 1Company overview

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Confidential: Not for distribution or publication

Adjusted EBITDANet sales

■ Largest and only national

wholesale distributor of

landscape supplies

– More than four times the size

of next competitor

– Approx. 10% market share

■ ~$17bn highly fragmented market

■ Serving residential and

commercial landscape

professionals

■ Complementary value-add

services and product support

■ Over 100,000 SKUs

■ 478 branches in 45 states and

five provinces1

2016 net sales mix

By product category By end market By construction sector

Company highlights

Key financials

SiteOne: transforming the landscape distribution industry

% margin 6.3% 6.3% 7.3% 8.1%

1 As of April 2, 2017

Source: Company filings, Management estimates

Irrigation33%

Fertilizer& Other

17%

Control Products

17%

Nursery12%

Landscape Accessories

11%

Hardscapes6%

Outdoor Lighting

4%Maintenance

43%

New Construction

39%

Repair & Upgrade

18% Residential54%

Commercial31%

Recreational & Other

15%

1,078 1,177

1,452

1,648

0

300

600

900

1,200

1,500

1,800

2013 2014 2015 2016

($ in m

illio

ns)

68 74

107

134

0

20

40

60

80

100

120

140

2013 2014 2015 2016

($ in m

illio

ns)

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Confidential: Not for distribution or publication

SiteOne plays a critical role in the professional landscape supply value chain

Thousands

of suppliers

Hundreds of thousands

of customers

Large: ~27% of 2016 net sales

■ >$200K in avg. annual

purchases

Medium: ~54% of 2016 net sales

■ $10K – 200K in avg. annual

purchases

Coast-to-coast

national network

Extensive

sales &

marketing

Rapid

product

launches

Fewer and larger

shipments

Broadest

product

offering

Superior

technical

expertise

Customer

loyalty

program

Trade credit,

sales leads

and training

SiteOne provides: SiteOne provides:

Critical business partner Small: ~18% of 2016 net sales

■ <$10K in avg. annual

purchases

One-stop shop

Source: Company data, Management estimates

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Confidential: Not for distribution or publication

We are the Only National One-stop Shop Provider in the Industry

Source: Management estimates, Company data; Wholesale outlets only

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Irrigation

Fertilizer

& Other

Control

Products Nursery

Landscape

Accessories Hardscapes

Outdoor

Lighting

% of 2016 Sales 33% 17% 17% 12% 11% 6% 4%

Key Products

Key Suppliers

Market Position #1 #1#1#1 #1 #1#1

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Confidential: Not for distribution or publication

SiteOne is poised for long-term growth and margin enhancement

Current strategy

Leverage strengths of both large and local company

■ Fully exploit our scale, resources and capabilities

■ Execute local market growth strategies

■ Deliver superior value to our customers and

suppliers

■ Close and integrate high value-added acquisitions

■ Entrepreneurial local area teams supported by

world-class leadership and functional support

Early innings of operational and commercial excellence

■ Category management

■ Pricing

■ Supply chain

■ Salesforce performance

■ Marketing

Value creation levers

1) Organic growth

2) Margin expansion

3) Acquisition growth

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Confidential: Not for distribution or publication

Position #1

Avg yrs

industry

expertise

% former

contractors /

golf super’int

Regional

VP11 24 18%

Area

Manager45 23 64%

Area

Business

Manager

34 19 59%

Branch

Manager460 15 44%

Outside

Sales Rep2 ~350 17 52%

Functional excellenceLocal leadership team Senior leadership team

■ Recently added top

industry talent from best-

in-class companies

■ Functional areas with

recent hires include:

Finance

Pricing

Category management

Marketing

Strategy

Supply chain

Name Experience

Doug BlackCEO & Director

John GuthrieEVP & CFO

Pascal ConversEVP, Strategy, Development & IR

Ross AnkerEVP, Category Mgmt, Marketing & IT

Briley BrisendineGeneral Counsel

Joseph Ketter SVP, Human Resources

Matt HartWest Division President

Jon KerrNorth Division President

Taylor Koch South Division President

Jim Slomka VP, Sales

Greg Weller SVP, Supply Chain

1 Excludes open positions. As of December 31, 2016

2 Includes Agronomic Sales Rep (ASR)

Source: Employee Survey Results, Company data

Proven management team driving performance and growth

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Confidential: Not for distribution or publication

Number of MSAs

Total MSAs

SiteOne

presence

#1 or #2 SiteOne

market position

All product

lines offered

Significant room to grow across geographies and products

■ Well positioned in large,

fragmented and growing

MSAs

– #1 or #2 local market

position in ~80% of

MSAs where SiteOne has

a presence

■ Significant “white space”

for growth

– SiteOne currently has a

presence in only ~46%

of total MSAs

– Full product line is

currently offered in only

~24% of the U.S. MSAs

where SiteOne has a

branch

Source: Company filings, Freedonia, Management estimates

Current 2014

381

176 139

31

1

3

12

381

177

142

43

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Confidential: Not for distribution or publication

Acquisitions are a key part of the value creation strategy

■ Strengthens our business

Geographic footprint

Product expansion

Market consolidation

Talent / capabilities

■ Significant synergies

Purchasing scale

Overhead leverage

Cross-selling

Branch network optimization

Commercial & operating best practices

Growth, margin

& cash flow

improvement

Strategic

acquisitions

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Confidential: Not for distribution or publication

2014 2015 2016 2017 YTD

Annualized sales1 ~$40M ~$230M ~$150M ~$95M

# branches added 18 50 29 20

Robust track record of acquisitions

Target Locations Strategic rationale

Ac

qu

isit

ion

s

sin

ce

IPO

Bissett 3 locations in NY Led to #1 nursery position in Long Island & NYC

Glen Allen 1 location in VA #1 nursery position in the Richmond metro

Loma Vista 2 locations in MO & KS #1 nursery position in the Kansas City metro

East Haven 1 location in CT Strengthened #1 nursery position in New Haven, CT

Aspen Valley 3 locations in IL #1 landscape accessories and #2 hardscapes position in Chicago metro

Stone Forest 1 location in GA Strengthened #1 hardscapes position in Atlanta metro

Angelo’s 2 locations in MI #1 hardscapes position in Detroit metro

AB Supply 12 locations in CA and NV Leading hardscapes platform in Southern California and Las Vegas

Evergreen 2 locations in NC and SC #1 nursery position in Myrtle Beach and strengthened existing nursery position in Raleigh

1 Trailing twelve month revenues in the year acquired

Source: Company filings, Press release

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Confidential: Not for distribution or publication

Chicago

Woodstock

Geneva

Wheaton

NapervilleAurora

Joliet

SiteOne

Shemin

Aspen Valley

Market example: Acquisitions made us a full-line supplier in Chicago

Lighting

5%

Nursery

12%

Irrigation

17%Hardscapes

19%

Landscape

Accessories

20%

Agronomics

32%

Irrigation

37%

Lighting

5%

Nursery

2%Agronomics

54%Landscape

Accessories

3%

SiteOne Chicago market pre-acquisitions (FY14) SiteOne Chicago market post-acquisitions (FY16)

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~10%

~90% opportunity

~$15bn1

A SiteOne is a leading player in industry consolidation

E Acquisitions are accretive and present significant profit growth potential

C Our pipeline is deep and expanding

B Significant sourcing advantage with 60+ associates scouting

D M&A team in place to execute larger pipeline

Robust pipeline of opportunities provides accelerated growth

1 Represents 90% of the ~$17bn professional landscape supply industry not covered by SiteOne

Source: Company data, Management estimates

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SiteOne’s 2017 outlook

Underlying market trends remain positive

Sales & marketing initiatives expected to accelerate market share gains

Gross margin expansion expected to continue

SG&A as % of net sales expected to decline slightly

Expected acceleration of M&A activity from a robust pipeline

2017 Adjusted EBITDA expectation of $155 million to $165 million

Source: Company data