Triathlons in UK in September 2026
Find triathlons in UK in September 2026 - filter by date, location or category, display on a map or use the advanced search to find your perfect race.
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- Sat 5 Sep 2026
- £215-£260
THE ROC ENGLAND
Face up to the mountain in one of Europe's most inspiring locations. From Windermere to Coniston to summit England's highest mountain, if you love a tough and rewarding challenge - you'll thrive.
- Recycling
- Plastic bottle free
- Music
- Chip timing
- Enter online
- Mountainous
- Event village
- Rural
- Mountains
- Sustainability policy
- Plastic-free event
- Age 18 & over
- 1.5 km lake swimming
- 92 km road cycling
- 18.5 km multi terrain running
- Sun 6 Sep 2026
- £75-£120
Helvellyn Triathlon & Aquabike
Take on one of the UK’s toughest triathlons – a legendary Lake District challenge where brutal climbs, wild beauty and sheer determination define every mile.
- Rural
- Mountains
- Age 17 & over
- Olympic triathlon
- Standard aquabike
- Sun 13 Sep 2026
- £73-£108
Aviemore Triathlon
Escape to the Cairngorms for an adventure triathlon in the scenic waters of Loch Morlich, then mountain biking and trail running in Glenmore Forest. Go Short Fast Durty or Long Hard Durty.
- Recycling
- Newcomers
- Event village
- Sustainability policy
- Age 15 & over
- Sprint triathlon
- Olympic triathlon
- Sun 20 Sep 2026
- £30-£97
Eton Dorney Triathlon & Swims
The Olympic venue, Eton Dorney, offers pan-flat, traffic-free roads and a beautiful clear lake for all levels of triathletes and swimmers to enjoy in an exclusive setting.
- Families
- Recycling
- Newcomers
- Dogs allowed at venue
- Event village
- Urban
- Park
- Rural
- Free venue entry
- Age 15 & over
- Super sprint triathlon
- Sprint triathlon
- Olympic triathlon
- Lake swim 4
- Sun 20 Sep 2026
- £55-£115
ATW St Neots Triathlon | Race 3
Stunning riverside venue! Swim in the beautiful River Ouse, cycle through scenic villages and run around Riverside Park in a triathlon or aquabike event of your choice.
- Newcomers
- Event village
- Park
- Sustainability policy
- Age 15 & over
- Super sprint triathlon
- Sprint triathlon
- Olympic triathlon
- Standard aquabike
- Sprint aquabike
- Sat 26 Sep 2026
- £75-£116
ATW Grafham Triathlon
Sprint or Standard Tri or Aquabike, in and around the beautiful, clean reservoir, on a flat course for all abilities with custom-designed medal, free photos and finish line goodies.
- Recycling
- Newcomers
- Event village
- Park
- Sustainability policy
- Age 15 & over
- Sprint triathlon
- Olympic triathlon
- Standard aquabike
- Sat 26 Sep 2026
- £58-£120
Dorney Triathlon | September
Take on this multi-activity event as an individual or as a relay, and enjoy the opportunity to race around the unique and inspiring Olympic venue! Great water quality and flat, scenic grounds.
- Recycling
- Newcomers
- Event village
- Sustainability policy
- Public transport links
- Age 15 & over
- Super sprint triathlon
- Sprint triathlon
- Olympic triathlon
- Sprint aquabike
- Standard aquabike