Triathlons & duathlons in Ontario
68 upcoming triathlons & duathlons across Ontario, with the deepest fields in Welland, Barrie, Toronto. Next up: YMCA Strong Kids Duathlon Campbellford on August 13, 2026.
Updated daily — every listing links to the organizer's official registration page.
68 races listed
YMCA Strong Kids Duathlon CampbellfordReg closes soon
Trent Hills, ON · Triathlon / duathlon
Toronto Island - Sat Aug 15 and Sun Aug 16Reg closes soon
Toronto, ON · Triathlon / duathlon · 25km
XTERRA Sleeping Giant - 2026
Thunder Bay, ON · Triathlon / duathlon · 46km / 20km / 11km / 40km
Subaru Triathlon Series - Owen SoundReg closes soon
Owen Sound, ON · Triathlon / duathlon · 41km / 51km
2026 Petawawa TriathlonReg closes soon
Petawawa, ON · Triathlon / duathlon · 25km
TRi KiDS Triathlon Series NIAGARA (PORT COLBORNE), ON
Port Colborne, ON · Triathlon / duathlon
Toronto Island - Sat Aug 16 and Sun Aug 17Date TBA
Toronto, ON · Triathlon / duathlon · 25km
YMCA Strong Kids Duathlon Cobourg
Cobourg, ON · Triathlon / duathlon
2026 Cornwall Youth Triathlon
Cornwall, ON · Triathlon / duathlon
2026 Cornwall Triathlon - Adult Day
Cornwall, ON · Triathlon / duathlon · 51km / 25km / 5km
Wasaga Beach - Sat Aug 23Date TBA
Wasaga Beach, ON · Triathlon / duathlon · 51km / 25km
Subaru Women's Triathlon FestivalDate TBA
Grimsby, ON · Triathlon / duathlon
Wasaga Beach - Sat Aug 29
Wasaga Beach, ON · Triathlon / duathlon · 51km / 25km
Subaru Triathlon Series 2026
ON · Triathlon / duathlon
Subaru Triathlon Series - Guelph Lake 2
Guelph, ON · Triathlon / duathlon
Lakeside - Sat Sept 6 and Sun Sept 7Date TBA
Lakeside, ON · Triathlon / duathlon · 25km / 51km
2026 MultiSport Canada Triathlon Series
ON · Triathlon / duathlon
Lakeside - Sat Sept 12 and Sun Sept 13
Lakeside, ON · Triathlon / duathlon · 25km / 51km
Barrelman Niagara Falls
Welland, ON · Triathlon / duathlon · 51km / 41km
2026 Triathlon Series Volunteer Portal
Barrie, ON · Triathlon / duathlon
HoHoHoliday 5K - Virtual EditionDate TBA
Canada, ON · Triathlon / duathlon · 5km
Superior Triathlon #1Date TBA
Thunder Bay, ON · Triathlon / duathlon · 8km
Superior Indoor Triathlon #2Date TBA
Thunder Bay, ON · Triathlon / duathlon · 8km
DU YOU KNOW HOW PAINFUL THIS WILBY?Date TBA
Waterloo, ON · Triathlon / duathlon · 25km / 50km / 75km / 8km
Gravenhurst - Sat June 13 and Sun June 14Date TBA
Gravenhurst, ON · Triathlon / duathlon · 51km / 25km
Rose City (Welland) - Sat June 27 and Sun June 28Date TBA
Welland, ON · Triathlon / duathlon · 25km
TRi KiDS Triathlon Series MILTON, ONDate TBA
Milton, ON · Triathlon / duathlon
Bracebridge - Sat July 11 and Sun July 12Date TBA
Bracebridge, ON · Triathlon / duathlon · 51km / 25km
PureKids Triathlon Series Powered by SubwayDate TBA
Windsor, ON · Triathlon / duathlon
Subaru Triathlon Series - NiagaraDate TBA
Grimsby, ON · Triathlon / duathlon
Lakeshore Women's TriathlonDate TBA
Port Elgin, ON · Triathlon / duathlon · 3km
Bluewater Triathlon and Duathlon -Date TBA
Sarnia, ON · Triathlon / duathlon · 51km / 25km / 41km
Barrie - Sat Aug 8 and Sun Aug 9Date TBA
Barrie, ON · Triathlon / duathlon · 25km
Multisport Canada - BracebridgeDate TBA
Bracebridge, ON · Triathlon / duathlon · 51km / 25km
Sydenham Triathlon & DuathlonDate TBA
Sydenham, ON · Triathlon / duathlon · 51km / 25km
Multisport Canada - Toronto IslandDate TBA
Toronto, ON · Triathlon / duathlon · 25km
Toronto Island - Sat Aug 19 and Sun Aug 20Date TBA
Toronto, ON · Triathlon / duathlon · 25km
Toronto Island - Sat Aug 17 and Sun Aug 18Date TBA
Toronto, ON · Triathlon / duathlon · 25km
Multisport Canada - LakesideDate TBA
Lakeside, ON · Triathlon / duathlon · 25km / 51km
Lakeside - Sat Sept 7 and Sun Sept 8Date TBA
Lakeside, ON · Triathlon / duathlon · 25km / 51km