Open water swimming season UK
Open water swimming is usually most comfortable from May to September, when many UK waters reach 15°C or more.
2026 main swimming season ends: Wednesday, 30 September 2026
Get a reminder 7 days before Open water swimming season UK
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Upcoming dates
| Event | Date | Countdown | Region / notes |
|---|---|---|---|
| 2026 main swimming season ends | Wednesday, 30 September 2026 | In 3 months | Wetsuit swimming can extend into October |
| 2027 main swimming season begins | Saturday, 1 May 2027 | In 10 months | Often 15°C+ by late spring or early summer |
| 2027 main swimming season ends | Thursday, 30 September 2027 | In 1 year 3 months | UK |
The main UK open water swimming season is a broad May to September window, not a fixed start date. Many swimmers look for water temperatures around 15°C or above for more comfortable swimming, although cold water risk still needs care. With a wetsuit, neoprene accessories and local knowledge, some swimmers extend the season from March to October. Conditions vary by lake, river, coast, weather and experience, so check local safety guidance before entering the water.
outdoor gear
Wetsuits, tow floats and wild swimming gear
Verified 14 May 2026
Questions
When is open water swimming season in the UK?
Broadly May to September for most casual swimmers, with colder wetsuit swimming possible either side.
What water temperature is comfortable for swimming?
Many swimmers use 15°C or above as a rough comfort guide, but ability, exposure time and weather matter.
Can I swim outdoors in March or October?
Yes, experienced swimmers often do, especially with a wetsuit, but it is colder and needs extra caution.