When buying compression socks in the UK, check for MHRA registration and a graduated mmHg rating. For everyday wear, 15 to 20 mmHg suits most people.
Stand in front of the compression sock shelf in a big pharmacy, or scroll through the results online, and the choice falls apart quickly. There are £5 "flight socks", £15 "support socks" and £40 "medical grade" stockings, in sizes from S to XL or by shoe size alone. Some packs say "graduated", some say "compression", and some say nothing useful at all.
First-time buyers often pick on price or colour, find the socks slide down or dig in, and decide compression doesn't work for them. Usually the socks were the problem.
Here's the rule we'd teach anyone buying their first pair:
The front of the packet sells, and the back of the packet tells. The useful information sits in the small print, if it's there at all.
This guide is a seven-point checklist for reading that small print. It covers compression level, graduation, MHRA registration, sizing, length, fabric, and what happens if the fit is wrong. It also explains when to go through the NHS instead, and who should check with a GP first. By the end, you'll be able to look at any pair and decide in a couple of minutes whether it's worth your money.
What should you look for when buying compression socks in the UK?
Look for a stated mmHg rating, confirmation that the compression is graduated, and MHRA registration. Then check that the socks are sized by calf measurement, come in a length that suits you, and are made from a hard-wearing fabric. Before you pay, read the returns policy. Those seven checks separate a pair that works from a tight sock with a medical-sounding label.
This page is a brand-neutral buying checklist for first-time buyers. If you already know what you want and are looking for where to order, our guide on where to buy compression socks in the UK covers that. If you're trying to match a pair to NHS prescribing guidance, see our guide to the style of compression stockings the NHS suggests.
1. What compression level should you buy?
Most people buying compression socks for the first time should choose 15 to 20 mmHg. That level suits long shifts on your feet, long flights, pregnancy swelling (with your midwife's agreement), and tired, heavy legs at the end of the day, and you don't need a prescription for it.
The mmHg figure tells you how firmly the sock squeezes at the ankle. If a pack doesn't give a number, you've no way of knowing what you're buying. Treat that as a reason to put it back. Firmer stockings exist, but they're mostly prescribed after a GP or nurse has checked your circulation, so they're not a sensible first purchase.
You may also see UK compression "classes" on prescribed hosiery. NHS hosiery guidelines from Bristol explain that there are two main compression standards used in the UK, British Standard and RAL, and a "Class 1" under one standard doesn't mean the same pressure as under the other. When you're buying for yourself, ignore the class and compare mmHg figures.
2. Is the compression graduated?
The compression should be graduated, which means firmest at the ankle and gradually easing towards the knee. That pattern helps blood and fluid travel back up the leg instead of pooling around the ankles. A sock that squeezes evenly from top to bottom, or tighter at the calf than the ankle, doesn't work the same way.
Look for the word "graduated" next to the mmHg rating. Be wary of products sold as "support" or "compression" socks with no mention of graduation or a pressure figure. They may feel snug, but you can't tell whether the pressure is in the right place.
3. Is it registered with the MHRA?
Check whether the socks are registered with the MHRA, the UK's medical device regulator. UK government guidance states that all medical devices must be registered with the MHRA before they can be placed on the market in Great Britain. Compression socks sold as medical devices fall under that rule, and the registration is what allows a seller to describe them as medical grade.
You'll usually find this information on the packaging, product page, or brand's FAQs. If you can't, email the seller and ask. A brand that's registered will tell you plainly.
Registration tells you the product has been placed on the UK market as a medical device. It doesn't mean every pair suits every person, so the fit and safety checks below still apply. Our knee-high compression socks are MHRA-registered at 15 to 20 mmHg, graduated from ankle to knee.
4. How is it sized?
Choose compression socks sized by calf circumference as well as shoe size. The pressure is applied around your ankle and calf, so a size chart based only on shoe size is guessing. Two people with the same shoe size can have calves several centimetres apart.
Measure the widest part of your calf first thing in the morning, before your legs have swollen during the day, and note your UK shoe size. As an example, our size guide has two sizes. Small fits UK shoe sizes 3 to 6 and a calf of 30 to 37 cm. Medium fits UK 6 to 9 and a calf of 36 to 43 cm. If you're between sizes, go up.
If your measurements fall outside a brand's chart, don't squeeze into the nearest size. A pharmacist can suggest alternatives. Our guide to how tight compression socks should be explains what a good fit feels like once the socks are on.
5. Which length do you need?
Knee-high compression socks are the right length for most people. They cover the ankle and calf, where swelling builds up, and they're far easier to put on than thigh-length stockings. The Bristol NHS guidelines note that below-knee stockings are the preferred choice because they're better tolerated than thigh-length, which helps people keep wearing them.
Thigh-length stockings and compression tights have their place, for example when varicose veins or swelling extend above the knee. That's a decision for your GP or nurse rather than a first purchase. If you're buying for everyday comfort, travel or long shifts, start with knee-high.
6. What is the fabric made of?
Look for a blend of nylon and spandex (also called elastane or Lycra). Spandex creates the stretch that produces compression, and nylon keeps the sock strong, smooth, and quick-drying. Cotton-rich blends feel soft at first but hold sweat and tend to lose their shape sooner.
Check the composition label for both a stretch fibre and a body fibre. If you know you react to latex, rubber, or certain dyes, read the full label and ask the seller before buying. Our socks are 80% nylon and 20% spandex, a blend that wicks moisture through long shifts and warm flights.
7. What happens if they don't fit, and how long will they last?
Read the returns policy before you buy, because most sellers won't take back compression socks that have been worn or tried on, for hygiene reasons. That makes measuring properly before you order important. Check how long you have to return unopened socks and who pays the return postage.
Think about lifespan as well as price. With daily wear, compression socks usually need replacing every three to six months, and an NHS leaflet from North Cumbria says people need new hosiery every 3 to 6 months to keep the right support. A £5 pair that's loose after two weeks costs more per wear than a well-made pair that lasts months.
If you'll wear them most days, two pairs let one dry while you wear the other. Our socks cost £30 for one pair, £54 for two and £72 for three, with free UK delivery over £50. Wash them in cold water and let them air-dry to make them last. Our guide on how to wash compression socks explains the routine.
Should you buy compression socks yourself or get them on the NHS?
Buy them yourself if you want 15 to 20 mmHg socks for everyday comfort, long shifts or travel. See your GP if you have a diagnosed condition, such as varicose veins with symptoms, venous leg problems or ongoing swelling. You may need prescribed stockings at a specific strength after an assessment.
NHS prescribing guidance from Bristol notes that compression hosiery for travel alone is not available on NHS prescription, so flight socks are usually something you buy. The same guidance notes that some pharmacists can take measurements for compression hosiery. A pharmacist is a good first stop if you're unsure of your size or level.
If your GP has already prescribed stockings, keep wearing those. A bought pair shouldn't replace something a clinician chose for a reason.
Who should check with a GP before buying compression socks?
Most healthy adults can buy and wear 15 to 20 mmHg compression socks safely. Some people should speak to a GP or pharmacist first, because compression presses on the arteries, nerves and skin as well as the veins:
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Peripheral arterial disease (PAD), or poor circulation in the legs. NICE explains that the reduced blood flow in PAD can be worsened by compression therapy.
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Diabetes, especially with swelling or reduced feeling in the feet. The NHS advises an urgent GP appointment or NHS 111 if you have diabetes and your feet, ankles or legs are swollen.
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Very swollen legs or peripheral neuropathy. An NHS leaflet from Sherwood Forest Hospitals lists very swollen legs, PAD and peripheral neuropathy among situations where stockings may not be suitable.
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Broken, infected or very fragile skin on the lower legs.
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Heart failure, unless your care team has said compression is fine.
Swelling in one leg with no obvious cause also needs checking before you buy anything. The NHS advises urgent advice in that situation too. Our full guide on who should not wear compression socks covers each condition in more detail.
Frequently asked questions
Are cheap compression socks worth buying?
Only if they pass the same checks as a more expensive pair: a stated mmHg rating, graduated compression and calf-based sizing. Many low-cost socks give no pressure figure, so you can't know what they're doing. A cheap pair that loses its squeeze within weeks often costs more per wear than a well-made pair that lasts months.
Are flight socks the same as compression socks?
Flight socks are compression socks marketed for travel, usually at the lighter end of the range. Whether a particular pair is any good comes down to the same checks: mmHg rating, graduation, and fit. Our guide on whether flight socks are the same as compression socks explains the overlap.
Can I buy compression socks from a pharmacy?
Yes. Most UK pharmacies stock some compression socks, and pharmacists can advise on whether compression is suitable for you. Some can also measure your legs. Check the packs on the shelf against the same checklist, because pharmacy stock varies from unrated travel socks to proper graduated compression.
What does "medical grade" mean on compression socks?
In the UK, "medical grade" generally means the socks are sold as a medical device and registered with the MHRA. That's different from "support" or "sports" socks, which may make no medical claims. Look for the MHRA registration and the mmHg rating together, rather than relying on the phrase alone.
How do I know when my compression socks have worn out?
Compression socks have worn out when they feel noticeably looser than when new, slide down by lunchtime, or bunch around the ankle. Thin patches at the heel or calf are another sign. With daily wear, most pairs reach that point within three to six months.
Your compression sock buying checklist
Before you buy compression socks in the UK, run through these seven checks:
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A stated compression level, with 15 to 20 mmHg for most first-time buyers
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Graduated compression, firmest at the ankle
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MHRA registration as a medical device
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Sizing by calf measurement as well as shoe size
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Knee-high length unless your GP advises otherwise
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A nylon and spandex blend that holds its shape
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A clear returns policy, and enough pairs to rotate if you'll wear them daily
If you have PAD, diabetes, very swollen legs, broken skin or heart failure, speak to your GP or pharmacist first.
When you're ready, measure the widest part of your calf in the morning and note your UK shoe size. Then hold our MHRA-registered 15 to 20 mmHg knee-high compression socks up against the same checklist, and check your size in the guide before you order.
