X0306 4 2017-11-21 0 0001650729 SiteOne Landscape Supply, Inc. SITE 0001244711 ANKER ROSS MANSELL OVERLOOK 300 COLONIAL CENTER PARKWAY, SUITE 600 ROSWELL GA 30076 0 1 0 0 EVP, Category Mgmt, Mktg & IT Common Stock 2017-11-21 4 M 0 17113 7.07 A 76394 D Common Stock 2017-11-21 4 S 0 17113 71.75 D 59281 D Stock Options (right to buy) 7.07 2017-11-21 4 M 0 17113 0.00 A 2025-01-06 Common Stock 17113 150189 D The price reported in column 4 is a weighted average price. The shares were sold at prices ranging from $71.50 to $72.24, 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. 209,126 options were granted on January 9, 2015, and vest and become exercisable ratably in five installments on each anniversary of January 9, 2015, subject to continued employment. Prior to the transactions reported on this Form 4, 41,826 of these options that remain outstanding had vested. /s/ Briley Brisendine, Attorney-in-fact for Ross Anker 2017-11-22