In most cases, a real silk pillowcase costs more than a satin pillowcase. Silk is a natural fiber (from silkworms) and it usually involves more labor intensive production and stricter quality grading (for example, mulberry silk and momme weight). Satin is not a fiber but a weave. It can be made from polyester, viscose, or cotton, which often makes it cheaper to produce.

In practice, many “satin” pillowcases sold in stores are polyester satin, so they are usually much cheaper than a 100 percent silk pillowcase. Price differences also depend on momme (thickness), finishing details (zipper, piping), certifications, brand, and size.