Silk pillowcases have moved from luxury hotel novelty to everyday self-care staple, with claims about less hair frizz, fewer sleep creases and better skin. Some of those claims are real, some are exaggerated, and the shopping labels do not help: thread count, momme, grade and silk type are used inconsistently, and many budget pillowcases are not pure silk at all. This guide explains what each term actually means, so you can tell a genuine silk pillowcase from a satin lookalike and choose the right weight for your sleep style.

For silk, the key quality measure is momme, written as mm, which measures the weight of silk per square metre: the higher the momme, the denser and more durable the fabric. A good silk pillowcase is typically 19 to 22 momme, which feels smooth and substantial without being heavy or hot, while 16 momme is lighter and cheaper but wears out faster, and 25 momme and above is very luxurious but can feel warm and costs significantly more. Thread count, which matters for cotton, is misleading for silk, because silk fibres are long and continuous, so a high thread count on a silk label often means the seller is borrowing cotton language to sound premium. If a listing shouts about thread count but never mentions momme, treat it with suspicion.

Mulberry silk, made from silkworms fed only mulberry leaves, is the most common high-quality silk for pillowcases, prized for its long, uniform fibres and smooth finish. Grade 6A is the highest grade of mulberry silk, with the longest fibres and fewest imperfections, while lower grades may feel slightly rougher or pill sooner. Pure silk means 100 percent silk, with no polyester or satin blend, and a genuine product should say so clearly on the label and care tag. Satin, by contrast, is a weave, not a fibre: a satin pillowcase can be made from polyester and still feel slippery, but it will not breathe like silk and it will not offer the same hair and skin benefits, so always check the fibre content, not just the word satin.

Silk's smooth surface creates less friction than cotton, which can mean less hair breakage, less frizz and fewer tangles overnight, especially for curly, fine or chemically treated hair. For skin, silk absorbs less moisture and skincare product than cotton, so your night cream stays on your face rather than soaking into the pillow, and the smooth surface may reduce sleep creases, though it will not erase wrinkles. Silk is also naturally temperature-regulating and hypoallergenic, which suits hot sleepers and allergy-prone users. It is not, however, a medical treatment: if you have persistent skin or hair problems, silk can help with friction, but it will not replace proper skincare or hair care.

Pillowcase size matters more than people expect: a standard pillowcase is about 50 by 75 centimetres, a queen is slightly longer, and a king is wider, so measure your pillow before ordering, because a too-tight case will bunch and a too-loose case will slide off. Closure type also matters: an envelope closure tucks the pillow inside and stays neat, a zip closure stays fully closed but can snag hair if the zip is exposed, and a simple open-end case is cheapest but slips most. Care is straightforward but specific: machine wash on a gentle cold cycle in a mesh bag, or hand wash, and air dry away from direct sun, never tumble dry on high heat. A silk pillowcase that is easy to wash is one you will actually keep clean.

A genuine 19 to 22 momme, 100 percent mulberry silk pillowcase typically costs more than a polyester satin case, and a price that looks too good to be true usually means a blend, a lower momme, or a smaller size. Red flags include no momme listed, no fibre content on the label, a shiny but stiff feel, and a burn test claim in marketing, which no reputable seller needs. Buy from sellers who state momme, grade and fibre content clearly, offer a return policy, and include care instructions. One good pillowcase, washed regularly, is a better investment than a cheap multipack that pills and thins within months.

For most sleepers, a 19 to 22 momme, Grade 6A mulberry silk pillowcase in the right size, with an envelope closure, is the sweet spot. Check momme before thread count, check fibre before shine, and you will get the hair and skin benefits silk is actually known for, without paying luxury prices for a polyester lookalike.