How to Enter

Register your interest for 2020!

The 2020 Children with Cancer UK Swim Serpentine will take place on Saturday 19 September. Register your interest now to make sure you're among the first to sign up for next year's open water swimming festival.

The 2019 swim was the biggest in the event's history, with thousands of swimmers taking to the water in the late summer sun.

If you're taking part in Children with Cancer UK Swim Serpentine, why not use your place in the swim to raise money for charity? Check out a list of charities that have places and, once you have secured a place in the event, you can set up a fundraising page with Virgin Money Giving – it takes minutes and will make sure your charity receives even more of the money you raise.

The London Classics

London Marathon Events have brought together the best marathon in the world, the world’s greatest cycling festival and the inspirational open water swimming event, Swim Serpentine, to create the London Classics, one of the world’s great sporting challenges.

The unique challenge requires participants to run the London Marathon, cycle 100 miles in the Prudential RideLondon-Surrey 100 and swim two miles at Swim Serpentine.

Visit our London Classics page for more information.

Swimmers with Disabilities

Swimmers with a disability are welcome to enter any of the events. If support or help on the day is needed, please contact

Wetsuit & tow-float hire

Wetsuits are optional when the water temperature is over 15 degrees. However, for safety reasons, all swimmers must either wear a wetsuit or use a tow-float for all Children with Cancer UK Swim Serpentine events.

Choosing your wave

The Children with Cancer UK Swim Serpentine events will comprise a number of waves (groups).

If you enter Children with Cancer UK Swim Serpentine, you will be able to choose your wave, so you'll be able to swim with friends and family if you’d like to. If you do not choose a wave, you will be allocated one according to your predicted finishing time.

Change of address

If you change your address after applying, please email with your name, date of birth, telephone number, old address and your new address.

Your address details will then be changed in our system and a confirmation will be emailed to you when this has been done.

Please do not call the helpdesk with changes of address as these can only be processed by email.

Age Group Prizes

Although the focus of the event is on having fun, prizes will be awarded to first, second and third-placed swimmers in each age category. Prizes will be sent out post-event.