Bedding Size: How to Choose the Right Fit for Your Mattress

When you buy bedding size, the exact dimensions of sheets, duvets, and pillowcases designed to fit specific mattress types. Also known as bed linens, it’s not just about style—it’s about function. If your fitted sheet keeps coming off or your duvet bunches up in the corners, you’re probably using the wrong bedding size. Most people assume a queen sheet fits a queen mattress. But that’s not always true. Mattress thickness varies—some are 8 inches, others are 16. A standard fitted sheet won’t hug a deep mattress. And if your duvet is too small, you’ll be pulling it up all night.

Mattress size, the standard dimensions of a bed frame and sleeping surface. Also known as bed dimensions, it directly controls what bedding size you need. Twin, full, queen, king—each has exact length and width measurements. But here’s the catch: duvet size, the outer dimensions of a comforter or duvet insert. Also known as bed cover, isn’t always labeled clearly. A king duvet might be too big for a queen bed, or too small if your mattress is extra thick. Then there’s pillowcase size, the opening that holds your pillow, usually matching standard, queen, or king pillow dimensions. Also known as pillow covers, and if it’s too tight or too loose, your pillow slips out or looks sloppy.

It’s not just about matching labels. A UK standard queen mattress is 150cm x 200cm, but a US queen is 152cm x 203cm. Brands vary. Some sheets claim to fit deep mattresses but only stretch to 14 inches. Others are made for European beds and won’t fit your UK frame. You need to measure your mattress—height, length, width—before buying. Look for fitted sheets with deep pockets (14-18 inches) if your mattress is over 12 inches thick. Duvets should hang 10-15cm over each side for a neat look without dragging on the floor. Pillowcases should snugly hold your pillow without bulging or gaping.

Getting this right isn’t luxury—it’s sleep quality. Wrinkled sheets pull on your skin. A loose duvet lets cold air in. A pillowcase that’s too tight crumples your pillow and messes up your neck. You don’t need fancy materials to fix this. You just need the right bedding size. The posts below show real examples—from how to measure your mattress without a tape, to why your ‘king’ sheets still don’t fit, to which brands actually label their sizes correctly. No fluff. Just what works.