How to size a winter coat online without endless returns

Buying a coat online should be easy, but it's one of the most commonly returned items. Sizes vary between brands, "oversized" and "slim fit" mean different things to different shops, and a coat that fits over a T-shirt might be tight over a jumper. With ten minutes and a tape measure, you can get it right far more often.

Step 1: measure yourself properly

Use a soft tape measure, keep it level and snug but not tight, and measure over the kind of thin top you'd normally wear.

• Chest (bust): around the fullest part, under the arms and across the shoulder blades.
• Waist: around your natural waist, usually just above the belly button.
• Hips: around the widest part, important for longer coats and parkas.
• Sleeve: from the centre back of your neck, over the shoulder and down to the wrist bone with your arm slightly bent. Some brands measure from the shoulder seam instead, so check the chart.
• Back length: if you care where the coat ends, measure from the base of your neck down your back to where you'd like the hem.

Write the numbers down in centimetres and inches. Most UK charts use both.

Step 2: measure a coat you already like

This is the most useful trick. Lay a coat that fits you well flat on a table, zipped up, and measure:

• Pit to pit: straight across the chest from one armpit seam to the other. Double it for the garment's chest measurement.
• Sleeve length from the shoulder seam to the cuff.
• Back length from the collar seam to the hem.

Many retailers give garment measurements, not body measurements, on their size charts. Comparing garment to garment is far more reliable than guessing from "M" or "L".

Step 3: read the size chart, not the label

• Check whether the chart is body or garment size. A chart that says "to fit chest 96–101cm" is a body measurement. One that says "chest 112cm" is usually the garment itself.
• Look for the fit description: regular, relaxed, slim, oversized. Oversized styles are deliberately roomy; many people size down in them.
• Watch out for non-UK sizing. Some marketplace sellers use Asian or EU sizes that come up smaller. Check the listing for a centimetre chart rather than relying on the letter size.

Step 4: allow room for layers

A winter coat needs to fit over what you'll actually wear in January, not what you're wearing when you order in October. As a rough guide, a coat chest measurement several centimetres bigger than your body chest gives room for a jumper; puffers and parkas often need a bit more because the padding takes up space inside. If the size chart sits right on your measurement and you'll wear thick knitwear, consider the next size up.

Try this: put on your bulkiest jumper and measure your chest over it. Use that figure when reading the chart.

Step 5: check the details that ruin a fit

• Sleeves: with arms by your side, cuffs should cover your wrist bone. Reach forward as if holding a steering wheel; if your wrists are exposed, the sleeves are too short.
• Shoulders: the shoulder seam should sit at or just past your shoulder edge. Too narrow and the coat pulls across the back when you move.
• Length: a longer coat is warmer but can be awkward on a bike or in a car. Hip-length suits most commutes.
• Hood: check whether it fits over a hat and whether it's removable.
• Zip and fastening: a two-way zip helps longer coats when sitting or cycling.

Step 6: use reviews wisely

Reviews often say "runs small" or "size up". Look for patterns rather than one comment, and give more weight to reviewers who mention their height, build or usual size. Photos from buyers show how a coat really sits, which product shots taken on models often don't.

Step 7: know the returns rules before you buy

When you buy online from a UK business, you normally have the right to cancel within 14 days of receiving the goods, and then another 14 days to send them back, as explained on gov.uk. That applies to most new clothing bought from traders, though you may have to pay return postage unless the retailer says otherwise. Private sellers on marketplaces aren't covered in the same way. Our article on UK consumer rights for online purchases explains this in more detail.

To keep the option open:

• Try the coat on at home over your usual layers, with tags still on.
• Don't wear it outside until you're sure.
• Keep the packaging until the return window has passed.

Ordering two sizes: is it worth it?

Some people order two sizes and send one back. It can work with retailers that offer free returns, but it ties up money and creates extra deliveries and returns. If you've measured yourself and a coat you already own, you'll usually only need one.

Quick checklist

1. Measure chest, waist, hips and sleeve over a thin top.
2. Measure a coat you already like, flat.
3. Compare with the garment chart, not the letter size.
4. Allow room for winter layers.
5. Check sleeves, shoulders and length.
6. Read reviews for sizing patterns.
7. Check the returns policy and keep tags on until you're sure.

Ready to choose? Our coats under £60 guide covers practical puffers, padded coats and gilets, and how to layer for a cold, wet commute explains what to wear underneath.