How to choose a silk pillowcase

Not all silks are equal, and the word on its own says nothing.

Mulberry silk comes from the Bombyx mori silkworm, farmed and fed on mulberry leaves. The cocoon is unwound into a single continuous thread, long and regular. That continuity is what produces a smooth surface and an even fabric.

Tussah silk, called wild silk, comes from undomesticated worms. The thread is shorter and more irregular, and the colour naturally beige. The fabric is more rustic and less smooth.

A product page should state “100% mulberry silk”. The wordings to avoid are “silk satin”, “synthetic silk”, “silk touch” and “silky feel”: none of them denotes silk. If the composition is not written plainly, assume it is not guaranteed.

Momme is the unit of weight specific to silk. It describes the density of the fabric: at equal surface area, the higher the number, the heavier and denser the cloth.

For a pillowcase, the values on the market generally run from 16 to 30 momme. Below 19, the fabric becomes very light and wears out faster in daily use. Above 25, it gains substance but also price and stiffness.

Be careful: a higher momme is not automatically better. It is a trade-off, not a score. The detail is in our article on what momme means.

This is the criterion that causes the most returns, and the easiest to check before buying.

Measure your pillow flat, without its case, width and length, then its thickness at the highest point. Thickness is the forgotten measurement: it explains why a case “in the right size” sometimes turns out too tight.

The full method, with the common French formats, is set out in our size guide.

Three systems exist, and they do not behave the same way at night.

For a use where the head and hair rest directly on the fabric, a flat closure is preferable. If the product page does not state the system, that is a fair question to ask before buying.

Silk is a protein fibre. It is not washed like cotton, and poor care shortens a pillowcase's life far more reliably than a middling weight.

What to check on the label or the product page:

• Machine washable or hand wash only. A case that machine washes at 30 °C in a laundry bag is considerably easier to live with.
• Type of detergent. An enzyme-free detergent is necessary: enzymes attack protein fibres.
• Drying. The tumble dryer is out, without exception.

We have set out the full method, temperatures and mistakes included, in how to wash a silk pillowcase.

The most subjective criterion, but not without practical consequences: silk has a lustrous drape that reacts strongly to the light in the room. A dark shade absorbs light and emphasises the matte side; a pale shade reflects it.

Advice on pairing shades according to how the bedroom faces is in our article on choosing a colour.

Two simple checks, once the pillowcase is in your hands.

Touch and temperature. Mulberry silk feels cool on first contact, then takes on body temperature. Polyester satin stays lukewarm and quickly becomes warm under the cheek.

How the fabric behaves. Silk follows the shape and falls softly. Polyester keeps a stiffness and slides as a single sheet.

The full comparison between the two materials, and the distinction between fibre and weave, is in silk or satin: what is the difference.

This needs to be clear, because many pages are not.

The mulberry silk fibre is long and smooth. Hair slides across it instead of catching, where the weave of cotton holds it. Silk also absorbs less moisture than cotton, which explains the cool feel on contact.

Those are material properties, observable and verifiable. They do not constitute a treatment, and a pillowcase, whatever it is made of, is not a skincare product. Be wary of pages promising a result on your skin or your hair: they are selling a promise, not a textile.

What momme should I choose for a first silk pillowcase?

22 momme is the most common compromise: dense enough to last, supple enough to drape well. It is the weight of our pillowcase.

Is a more expensive silk pillowcase necessarily better?

No. Price depends on weight, thread quality and finishing, but also on margin and positioning. Compare the composition and the momme before the price.

Does the silk need to be on both sides?

Some pillowcases have silk on one side only, the other being cotton. That is cheaper, but the face in contact changes depending on how the pillow sits. Check the composition of both sides.

How long does a silk pillowcase last?

Almost entirely a matter of care. A properly washed case lasts several years; the same case put through a tumble dryer deteriorates within months. The seams give way before the fabric.

Is silk suitable in summer?

It absorbs little moisture and stays cool on contact, which makes it pleasant in warm weather. That is a property of the fibre, not air conditioning.