Fabrics and care · 8 October 2026 · 3 min read
What do pre-shrunk and sanforised mean on a label?
What does sanforised mean? A mechanical pre-shrinking finish, how it differs from a looser pre-shrunk label and whether to pre-wash fabric anyway.
InspirationThe meaning
Sanforised fabric has been through a mechanical pre-shrinking process at the mill. The cloth is dampened and pressed lengthwise against a thick, stretched rubber belt, so its threads are pushed closer together before it is sold. That takes up most of the shrinkage that would otherwise happen in the first few washes, and the finished garment keeps its size far better than one made from untreated cotton.
The word comes from Sanforized, a trademark registered by an American shirt maker in the 1930s for the process developed by its engineer, Sanford Cluett. It is still a licensed name for fabrics that meet a stated limit, but sellers now use sanforised, or sanforized, for compressive pre-shrinking in general.
Pre-shrunk is a looser word
Pre-shrunk simply says that some shrinking was done before sale. It may mean sanforising, a wash, a steam finish or a relaxing treatment, and there is no single standard behind it. On unstitched suit labels the phrase can be little more than reassurance. Sanforised is a more specific claim; pre-shrunk tells you less. Our guide to reading an unstitched suit label covers the other terms printed alongside it.
How much movement may still be left
Neither label means a garment can never change size. These are the places where movement usually remains.
- Across the width: compressive shrinking controls the length best, and the width can still move a little.
- Heat: hot washes and tumble drying can shrink even treated cotton.
- Other parts of the outfit: linings, laces, borders and thread may not be pre-shrunk at all, and can shrink at a different rate from the main fabric.
- Embroidered areas: dense stitching can draw the cloth in differently from plain areas.
Should you still pre-wash before stitching?
For a sanforised cotton on its own, pre-washing matters less than for untreated cloth. It is still sensible when the outfit combines fabrics, when the lining or trims are untreated, or when you want to check that a deep colour does not run. Always follow the fabric label. Our article on whether to pre-wash fabric before stitching gives the method, and drying clothes without fading or shrinking helps keep a finished outfit its size.
Where you see the label
You are most likely to find sanforised on cotton shirting, twill, denim and some cotton suiting and cambric, less often on lawn. If your fabric carries the word, mention it when you send photos for Stitching Only, along with whether you have washed it. We confirm the fabric is suitable before you post anything. Start a stitching-only quote.
Common questions
Does pre-shrunk fabric still shrink?
It can, a little. Pre-shrinking takes out most of the movement, not all of it, and hot water or a tumble dryer can still shrink the garment. Washing and drying as the label says keeps it closest to its size.
Is sanforised the same as mercerised?
No. Sanforising is a mechanical process that controls shrinkage; mercerising is a caustic soda treatment that adds sheen, strength and dye depth. A cotton can have either, both or neither.
Is sanforised fabric always cotton?
Mostly cotton and cotton blends, and some linen. Synthetic fabrics such as polyester shrink very little in normal washing, so they rarely carry the label.
