Wetsuit Thickness Guide: What to Wear and When in UK Waters

Whether you're paddling out at Fistral, chasing waves at Thurso East, or catching a swell at Croyde, one thing every UK surfer knows — the sea doesn't mess around. Choosing the right wetsuit thickness isn't just about comfort, it's about staying in the water longer and surfing better. Here's your no-nonsense guide to wetsuit thickness for UK conditions.

Understanding Wetsuit Thickness

Wetsuit thickness is measured in millimetres (mm) and usually shown as two or three numbers — for example, 5/4/3mm or 3/2mm. The first number is the thickness across the chest and back (the core), and the second (and third) refer to the arms and legs. The thicker the neoprene, the warmer the suit — but also the less flexible, so it's all about finding the right balance for the conditions.

UK Sea Temperatures by Season

UK sea temps vary significantly depending on where you're surfing — Cornwall is warmer than Scotland year-round — but here's a general guide for the most popular surf regions:

Which Wetsuit Thickness Do You Need?

🌊 6/5mm or 6/5/4mm — Winter Warriors (Below 8°C)

When: December to February, especially Scotland, Northumberland, and exposed Atlantic coasts.
Where: Thurso East, Coldingham Bay, Scarborough.

This is full cold-water armour. You'll want a hooded suit, 5mm gloves, and 5mm boots to go with it. If you're surfing in Scotland in January, don't cut corners here — hypothermia is a real risk.

💡 We don't currently stock 6/5mm suits, but our 5/4mm range is the next best thing for extreme cold — pair with gloves, boots and a hood for maximum warmth.

🌊 5/4mm or 5/4/3mm — Cold Water Comfort (8–12°C)

When: November through March across most of England and Wales; October–April in Scotland.
Where: Newquay, Croyde, Porthcawl, Tynemouth.

The UK winter workhorse. A good 5/4mm with sealed seams will keep you comfortable for a full session. Add 3mm gloves and boots and you're sorted. This is the suit most UK surfers spend the most time in.

🛒 Shop our 5/4mm wetsuits:
Mens 5/4mm Winter Wetsuit FAZE GBS Back Zip | Womens 5/4mm Winter Wetsuit KONA GBS Back Zip | Womens 5/4mm Winter Wetsuit FAZE GBS Back Zip

🌊 4/3mm — Spring & Autumn Sweet Spot (12–15°C)

When: March–May and September–November in SW England and Wales; summer in Scotland.
Where: Fistral Beach, Saunton Sands, Llangennith, Belhaven Bay.

Spring and autumn deliver some of the best surf in the UK — consistent swells, fewer crowds, and manageable temps. A 4/3mm is the go-to for these shoulder seasons. You might want thin boots in early spring, but by October you'll be reaching for the gloves again.

🛒 Shop our 4/3mm wetsuits:
Mens 4/3mm Spring Wetsuit FAZE GBS Back Zip | Womens 4/3mm Spring Wetsuit FAZE GBS Back Zip

🌊 3/2mm — Summer Sessions (15–18°C)

When: June–August in SW England and Wales; late summer in Scotland.
Where: Newquay, Croyde, Perranporth, Polzeath.

The UK summer suit. You'll be comfortable without boots or gloves on warmer days, though early mornings can still feel fresh. A quality 3/2mm with good flexibility is ideal for longer sessions when the sun's out and the crowds are in.

🛒 Shop our 3/2mm wetsuits:
Mens 3/2mm Summer Wetsuit ICON GBS Back Zip | Mens 3/2mm Summer Wetsuit ICON GBS Chest Zip | Womens 3/2mm Summer Wetsuit FAZE Full Length

🌊 2mm Shorty or Springsuit — Peak Summer Only (Above 18°C)

When: Occasional heatwave weeks in July–August, primarily in Cornwall and Devon.
Where: Watergate Bay, Sennen Cove, Bantham.

Rare but glorious. On those exceptional summer days when the sea hits 18°C+, a shorty or springsuit works — but keep a 3/2mm in the van just in case. UK weather has a sense of humour.

🛒 Shop our shorties:
Womens 3/2mm FAZE Shorty | Kids 3/2mm FAZE Shorty | Kids (Toddler) 3/2mm FAZE Shorty

Quick Reference Chart

Final Tips for UK Surf Trips

• Always check the sea temperature for your specific break before you go — apps like Magic Seaweed or Surf Forecast include water temp data.
• Seam quality matters as much as thickness. Look for glued and blind-stitched (GBS) or liquid-taped seams for cold UK waters.
• Rinse your suit in fresh water after every session — salt and sand degrade neoprene fast.
• Layer up on the beach — a changing robe is non-negotiable for UK surf trips, whatever the season.

🛒 Complete your kit:
3mm Adult FAZE Wetsuit Glove with Gripflex | 3mm ICON Wetsuit Surf Cap | Changing Mat + Wetsuit Bag

Ready to hit the water? Browse our full surf collection at Hairy Coconuts — built for those who live for the ocean, whatever the forecast.