Thames Marathon 2025

Sunday 10th August 2025


Event Details


THAMES HALF MARATHON – Approximately 5.5km including stops 
All swimmers will have the option to either walk/run to the Half Marathon start (this is just for fun, run times will not be recorded) or to be transported by coach. The swim is split into 3 sections. Swimmers will be required to exit the water at the 2 locks (Hurley at 1.5km and Temple at 3.2km) where drinks and energy snacks will be available.
Non-wetsuit places are limited, they do not need to be approved. 

THAMES MARATHON MID-DISTANCE – Approximately 9km including stops 
The swim is split into 3 sections. Swimmers will be required to exit the water at the 2 locks (Hurley at 5km and Temple at 6.7km) where drinks and energy snacks will be available.

THAMES MARATHON – Approximately 13km including stops 
The swim is split into 4 sections. Swimmers will be required to exit the water at the 3 locks (Hambleden at 3.8km, Hurley at 9km and Temple at 10.7km) where drinks and energy snacks will be available.

THAMES MARATHON RELAY – Approximately 13km including stops 
The Thames Marathon Relay is a team event for 3 people (swim distances approx 4km/5km/4km). Each person will swim one section of the course, and walk the other 2 sections. All 3 team members will be taken to the start of the course together.

NON-WETSUIT PLACES (9KM & 13KM)
There are a limited number of 9km and 13km places open to non-wetsuit swimmers, subject to experience and ability. This is to adhere to our safety plan. Wetsuits are important for retaining heat and providing buoyancy. If you would like a non-wetsuit place select the non-wetsuit option below and your application will be assessed by the events team for approval. Wetsuits for the Thames Marathon can be sleeveless, but must be below the knee. 

CUT-OFF TIMES AND TOW FLOATS
There will be a cut-off time of 6½ hours for the 13km distance (including relay), 5 hours for the 9km distance and 3½ hours for the 5.5km distance.
Tow floats will be compulsory for ALL swimmers. There is an opportunity to buy a tow float during the registration process.

CHARITY PLACES

We are pleased to be working with Level Water as our Official Charity Partner. Level Water give children with disabilities the opportunity to learn to swim. They believe that from physical development to social and emotional confidence, swimming is a vehicle to change children's lives for the better.

Charity places are available for £20 - please register for your charity place directly through Level Water.

REGISTER FOR CHARITY PLACE

Entry Options - Age 18 & over on Sun 10 Aug 2025
Thames HALF Marathon 5.5km
Available EARLY BIRD TIER 1 £99.00 Enter
+Booking Fee : £4.50

Both wetsuit and non-wetsuit should enter using this option

Thames Marathon WETSUIT PLACE 9km
Available EARLY BIRD TIER 1 £119.00 Enter
+Booking Fee : £4.50
Thames Marathon NON-WETSUIT PLACE 9km
Available EARLY BIRD TIER 1 £119.00 Enter
+Booking Fee : £4.50
Thames Marathon WETSUIT PLACE 13km
Available EARLY BIRD TIER 1 £134.00 Enter
+Booking Fee : £4.50
Thames Marathon NON-WETSUIT PLACE 13km
Available EARLY BIRD TIER 1 £134.00 Enter
+Booking Fee : £4.50
Thames Marathon 3-PERSON RELAY (4km/5km/4km)
Available EARLY BIRD TIER 1 £200.00 Enter
+Booking Fee : £4.50
Refund Policy

Please carefully read clause 5 (cancellation by you) and clause 6 (cancellation by the organisers) of our terms and conditions

https://henleyswim.com/terms-and-conditions/

Dates
Starts
Sun 10 Aug 2025 at 07:00
Contact Info
Henley Swim
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Alexandra entered on Tue 12 Nov 2024 09:37
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