X0306 4 2017-11-28 0 0001650729 SiteOne Landscape Supply, Inc. SITE 0001672120 Ketter Joseph MANSELL OVERLOOK 300 COLONIAL CENTER PARKWAY, SUITE 600 ROSWELL GA 30076 0 1 0 0 Senior VP, Human Resources. Common Stock 2017-11-28 4 M 0 2500 12.84 A 7716 D Common Stock 2017-11-28 4 S 0 2500 71.67 D 5216 D Stock Options (right to buy) 12.84 2017-11-28 4 M 0 2500 0.00 A 2025-07-27 Common Stock 2500 55591 D The price reported in column 4 is a weighted average price. The shares were sold at prices ranging from $71.66 to $71.68, inclusive. Upon request by the SEC staff, the issuer, or any security holder of the issuer, full information regarding the number of shares purchased or sold at each separate price will be provided. These options were granted on July 27, 2015, and vest and become exercisable ratably in five installments on each anniversary of July 27, 2015, subject to continued employment. Prior to the transactions reported on this Form 4, 23,236 of these options had vested. /s/ Briley Brisendine, Attorney-in-fact for Joseph Ketter 2017-11-29