Pilates Sock Sizing Guide UK: What Size Grip Socks to Buy
By the Curve MCR team, Manchester · Updated 25 August 2026
Curve MCR grip socks are one size, designed to fit UK 3-8 (EU 36-42, roughly US women's 5-10). The stretch in the cotton-rich knit does the sizing for you: it hugs a size 3 without bagging and reaches a size 8 without straining. If you're inside that range, you don't need to make a decision - and that's the point.
Why grip socks are often one size
A grip sock has one job that ordinary socks don't: keeping the silicone sole exactly under your foot while you move (here's the full difference between grip socks and regular socks). That means the knit has to fit close - a loose sock slides against your skin no matter how good the grip beneath it is. Sock makers solve this in one of two ways: sized ranges (like shoes) or a single high-stretch knit engineered around the middle of the market. Both approaches are common; ours is the second, because it pairs with the way we knit. Curve socks use an extra yarn, so the knit is dense enough to recover its shape wash after wash - that recovery is what lets one sock genuinely fit a five-size range rather than merely stretch across it.
The size conversion table
| UK | EU | US (women's) | Curve fit |
|---|---|---|---|
| 3 | 36 | 5 | Fits - snuggest end |
| 4 | 37 | 6 | Fits |
| 5 | 38 | 7 | Fits - centre of range |
| 6 | 39 | 8 | Fits |
| 7 | 40.5 | 9 | Fits |
| 8 | 42 | 10 | Fits - fullest end |
How a grip sock should feel on
Close, like a second skin, with no spare fabric anywhere. Run this three-point check the first time you wear a pair:
Heel seated. The sock's heel pocket should sit exactly on your heel, not ride up the achilles. If it drifts in wear, the sock is too big for you or the knit has no recovery.
No bagging at the toes. Spare fabric at the toe ends up folded under your foot mid-class. A proper knit stretches to your length without leaving a flap.
Cuff stays put. The ribbed cuff should hold without digging in. You shouldn't think about your socks between the warm-up and the final stretch - that's the whole job.
At the edges of the range
UK 2.5-3: you're at the snug end, which for a grip sock is the right problem to have - snug grips better than loose. The knit relaxes slightly after the first wear and wash.
UK 8: you're at the full end and the stretch is engineered to reach you comfortably. Above UK 8, our current range honestly isn't the right fit - larger sizes aren't something we make today (watch this space).
Wide or high-arched feet: stretch knits fit by volume, not just length, so most wide-footed pilates-goers inside UK 3-8 find one-size socks fit better than sized cotton socks that only come in length steps.
Do they shrink?
Not if you wash them as intended - 30 degrees, air dry (the full care routine is here). Heat is what shrinks cotton-rich knits, and heat is already off the menu because it damages the grip. Follow the care label and the fit on day 90 matches day one.
New to the reformer as well as the sizing? Whether you need grip socks for reformer pilates covers studio rules, and all ten colourways are here.
Frequently asked
What size grip socks should I buy in the UK?
If you wear UK 3-8, Curve MCR grip socks are one size and will fit - the stretch knit adapts to your foot. No size decision needed.
What is UK 3-8 in EU and US sizes?
EU 36-42, roughly US women's 5-10.
Should grip socks be tight or loose?
Close-fitting, always. The silicone sole can only grip the floor if the sock isn't sliding against your foot. Snug beats loose every time; genuinely tight (digging cuff, strained toe) means the sock is undersized for you.
Do Curve MCR socks come in men's sizes?
Our one-size sock fits up to UK 8, which covers many men's sizes but not all. Larger sizes aren't in the range today.
Do grip socks stretch out over time?
A dense, quality knit recovers its shape between wears and washes. Thin knits lose recovery fastest - if a sock bags at the heel after a month, the knit has failed, not your washing.