Thames Marathon 2022

Sunday 14th August 2022

A future version of this event is now available here Thames Marathon 2023 on Sun 13 Aug 2023
Event Details

The Thames Marathon is an endurance swim between Henley-on-Thames and Marlow. It covers a beautiful stretch of the Thames and has become one of open water swimming's most prestigious marathon swims.

The Event Village and Parking will be in Marlow, swimmers will be transported by coach to the full or half distance start, and will swim back to Marlow. There is also the option to walk or run to the start of the half-marathon. 

This year we will be offering a choice of two distances:
THAMES HALF MARATHON – Approximately 5.5km including stops 

***Due to popular demand we have managed to release a small number of additional places for the previously sold out Thames Half Marathon. However as these places are late entries and were not in our original plan, we cannot guarantee a medal for this event. 

If you would like to register to swim, and donate the cost of your medal to our partner charity SwimTayka, then please use the link below to confirm your place. We would ask that at the end of your swim you do not pick up a medal (as there may be swimmers finishing after you who registered earlier than you), if we have any medals left when all swimmers have finished we will distribute them. 

If the medal is your main reason for swimming this event, then maybe don't take the risk, and swim with us next year instead. ***

The Thames Half Marathon is a 5.5km endurance swim finishing in Marlow. 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 for a small additional fee. 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.
Just like the full distance, non-wetsuit places will be limited, but they will not need to be approved. Once the non-wetsuit places are full this will show on the entry system, and only wetsuit places 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. 

Wetsuit places

To apply for a wetsuit place click Enter on the Wetsuit Category below. You will be asked to select your wave, please do so based on the following criteria: 

Note that waves will be set off in reverse order from 10 to 1

  • Waves 1, 2, 3 & 4 - these waves are ideal for swimmers who are seeking a faster time and who expect to complete the course in under 4 hours (approximately equivalent to a sub 27 minute mile pace). If you expect your time to be under 3½ hours, please select wave 1, between 3½ and 4 hours select wave 2, 3 or 4.
  • Waves 5-10 - these waves will be mixed ability waves. If you do not consider yourself a racing swimmer, please select one of waves 5 to 10

Non-wetsuit places 

** Non-wetsuit places have now been filled. Please add your name to the waiting list and we will contact you if a place comes available **

There are a limited number of places open to non-wetsuit swimmers, subject to experience and ability. This is to minimise the risk to our safety plan. Wetsuits are important for retaining heat and providing buoyancy. If you would like a non-wetsuit place your application will be assessed by the events team for approval. 


We are pleased to be working with SwimTayka as an Official Charity Partner for the event this year.  We have collaborated with them to raise vital funds that will help reduce drowning in underprivileged parts of the world. Sign up for a FREE Charity Place today and pledge to raise money which will allow them to provide free swimming lessons to a much-needed part of the world, to help save lives from drowning and inspire children through swimming.  Each charity place swimmer will receive a fundraising pack and lots more support from the charity. 

If you wish to swim with a friend or as part of a group, please make sure that you all select the same wave. There will be a cut-off time of 6 and a half hours for the full distance and 3 hours for the half distance, where all swimmers will need to be out of the river. If you anticipate that you will take longer than this, please contact before entering

Tow Floats will be compulsory for all swimmers, both wetsuit and non-wetsuit for both the half and full distance. There is an opportunity to buy a tow float during the registration process.

Entry Options - Age 18 & over on Sun 14 Aug 2022
Entries closed
There are no options available at this time please check back later

Refund Policy

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

Sun 14 Aug 2022 at 07:00
Contact Info
Henley Swim
01491 577922
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Post Code : SL7 2AE