15-20 mmHg vs 20-30 mmHg: Which Compression Level Is Right for You?

What “mmHg” actually means

mmHg stands for millimetres of mercury, the same unit used to measure blood pressure. On a pair of compression socks, the two numbers describe the pressure range applied at the ankle — for instance, between 15 and 20 millimetres of mercury for the lighter range, or between 20 and 30 for the firmer one. According to MedlinePlus, this same unit appears widely in clinical and consumer pressure measurement.

The pressure isn’t the same all the way up the leg. With graduated compression, the highest pressure is at the ankle, and the pressure gradually decreases as the fabric moves up toward the knee. That’s by design: it’s the lowest part of the leg that has the most work to do against gravity, so that’s where the support is concentrated. We have a full explainer on graduated vs. uniform compression if you want to dig in.

15–20 mmHg: the everyday standard

15–20 mmHg is what most people picture when they think of an over-the-counter compression sock. It’s firm enough to be noticeable when you put it on, but gentle enough to be comfortable for a full day of wear.

Common reasons Canadians choose 15–20 mmHg:

• Long days at a desk where the legs sit still for hours
• Short and medium domestic flights, road trips, and train journeys
• General “heavy leg” feeling at the end of the day
• Mild ankle puffiness after long periods of standing or sitting
• Daily wellness support, particularly in warmer months
• A first introduction to compression hosiery

If you’ve never worn compression before, 15–20 mmHg is usually the most sensible starting point. The BuraCare 15–20 mmHg pair is designed for exactly this kind of everyday use — light enough to forget you’re wearing it within an hour, supportive enough that you notice the difference at the end of a long day.

What 15–20 mmHg is not

It’s not intended to replace medical advice or to treat a diagnosed condition. If you have persistent symptoms — significant swelling, leg pain, visible discoloration, a history of clots — that’s a conversation for a Canadian healthcare provider, not a sock to pick up at the store.

20–30 mmHg: firmer support

20–30 mmHg is a noticeable step up. The fabric grips the ankle more firmly, and the support is more present through the whole calf. Many people describe it as feeling like “the socks are doing something” from the first minute on.

20–30 mmHg is more commonly chosen for:

• Healthcare workers on 12-hour shifts (see our guide for Canadian nurses)
• Post-exercise recovery for runners and athletes
• Long-haul international flights from Canada to Europe or Asia
• People with more noticeable everyday leg fatigue or mild swelling
• Specific conditions, with healthcare-professional guidance (varicose veins, certain forms of mild oedema)

The BuraCare 20–30 mmHg pair is designed for exactly this profile of wearer. If you know your day is going to be hard on your legs, this level gives you noticeably more support than the 15–20.

Why a firmer sock isn’t automatically “better”

A higher mmHg value just means more pressure, not more benefit. Choosing 20–30 when 15–20 is what your day calls for can feel unnecessarily tight, and that often translates into a sock that gets kicked off after lunch. The best level is the one that matches the demands of your actual day.

Side-by-side comparison

How to choose between them

Think of it as a four-question filter:

1. What does your day actually demand of your legs? Eight hours seated at a desk is a very different day than eight hours behind a hospital ward.
2. Have you worn compression before? If this is your first pair, 15–20 mmHg is almost always the comfortable place to start.
3. Are you addressing a specific symptom or condition? If yes — persistent swelling, varicose veins, post-surgical considerations — that’s a conversation with a Canadian healthcare provider, who may suggest 20–30 or higher.
4. How warm or cool is your environment? A 15–20 pair tends to feel more comfortable through a hot Toronto summer; a 20–30 pair can feel great in a cool clinic or aircraft cabin.

If you still aren’t sure, two practical paths work well. One is to start with a single pair of 15–20 and live with it for a week. Most people know within a few days whether it’s enough. The other is to pick up a value pack in the level you suspect, so you have a clean pair ready while another is in the wash.

Canadian prescription & insurance notes

This catches a lot of Canadians off guard, so it’s worth being clear:

• You do not need a prescription to buy 15–20 mmHg or 20–30 mmHg compression socks in Canada. They’re widely sold over the counter.
• You usually do need a prescription to claim them under extended health insurance. Most Canadian private health plans require a written prescription from a qualified healthcare provider before they’ll reimburse 20–30 mmHg (medical-grade) hosiery.
• For higher pressure levels (30–40 mmHg and above), a prescription and professional fitting are typically required regardless of insurance, because the higher pressure isn’t appropriate for everyone.

For a deeper look at how Canada’s patient-information landscape describes compression, the Thrombosis Canada patient resources are a good reference point.

Frequently asked questions

Is 20–30 mmHg always better than 15–20?

No. “Better” depends on what you need. For most everyday situations — sitting at a desk, light leg fatigue, travel under four hours — 15–20 mmHg is the more comfortable choice. 20–30 is firmer and is more often chosen for harder days on the legs or under medical guidance.

Can I wear 20–30 mmHg socks without a prescription in Canada?

Yes, you can buy and wear them without a prescription. A prescription is generally required if you want your Canadian extended health insurance to reimburse the purchase.

Will 15–20 mmHg help with mild ankle swelling?

Many people choose 15–20 mmHg to support circulation during long days of sitting or standing, which is often when mild ankle swelling appears. If your swelling is persistent or one-sided, that’s worth discussing with a healthcare provider.

Can I switch back and forth between 15–20 and 20–30?

Some people own both: a 15–20 pair for desk days and a 20–30 pair for travel or harder shifts. There’s nothing wrong with that, as long as both fit you correctly and you’re comfortable in each.

What size of either level should I order?

Size is determined by your ankle and calf circumference plus your leg length, not by your shoe size alone. Walk through our sizing guide before ordering.

This article is general information, not medical advice. For persistent leg symptoms or a specific condition, please consult a Canadian healthcare provider.