Seyva

We check the conditions. You enjoy the water.

Sea-swimming guide

What should I wear for sea swimming?

Choose clothing around the water temperature, wind, time in the water, visibility and your own response to cold—not the air temperature alone.

Quick answerThere is no single clothing choice for every swimmer. A well-fitting wetsuit may help retain warmth and add buoyancy, while a bright hat, tow float and warm layers for afterwards can improve visibility and reduce cooling. Your clothing does not remove the need to assess the water and the route.

Plan for the water temperature

Sea temperature can lag behind changes in air temperature. Cold water may affect breathing and movement quickly, and wind after you exit can increase cooling. Read the sea-temperature information when available, but remember that personal response, immersion time and clothing fit vary.

Visibility and flotation are separate questions

A brightly coloured hat or tow float can make a swimmer easier to see, but a tow float is not a substitute for a buoyancy aid and is not designed to remove every risk. Follow local advice and choose equipment you can use without restricting your movement.

Prepare to change and warm up

Put dry layers, a hat and a drink where you can reach them quickly. Know where you will leave the water if you start to feel cold, tired, unwell or unable to control your breathing. Do not use somebody else’s time in the water as your benchmark.

Before you go

  • Check sea temperature and wind as well as the forecast air temperature.
  • Use visible equipment appropriate to the location and activity.
  • Have warm, dry layers ready before entering the water.
  • Set a shorter first session if you are not used to the temperature.
  • Leave the water if your breathing, coordination or judgement changes.

Useful next checks

Sea temperature and wetsuit guide · Sea-swimming conditions · RNLI open-water swimming advice

Written and reviewed by Ollie BartlettFounder of Seyva and a sea swimmer and paddleboarder based near Worthing. Reviewed 16 September 2026. Seyva is a planning aid, not professional safety advice.