Can I call my T-shirts “pre-shrunk”?

Short answer: "Pre-shrunk" implies that the fabric or garment has been treated so it will shrink little further in normal care. It does not mean zero shrinkage, but customers expect only a small change. Any product claim in advertising or on labels should be truthful and supported by evidence, so before using it, ask what process was used, such as compacting or garment washing, and test the finished garments for dimensional change with ISO 5077 after a washing and drying procedure from ISO 6330 that reflects your care label. Set an internal limit for what you will call pre-shrunk, for example a few percent in length and width, test every lot, and consider wording such as "pre-shrunk to minimise shrinkage" with care instructions. If test results vary widely, do not use the claim until the fabric is consistent.

What the claim implies

• A treatment intended to reduce further shrinkage.
• Small dimensional change in normal care, not none.
• A customer expectation that size will stay close to the label.

Evidence to hold

• A description of the process from the supplier.
• Test reports of garment dimensional change with ISO 5077 and ISO 6330, prepared and measured with ISO 3759.
• Results for each bulk lot, not only development samples.

Wording

• Avoid absolute promises such as "will not shrink".
• Pair the claim with clear care instructions.
• Make sure the care label procedure matches the tested procedure.

A worked example

The brand tests three lots of the supplier's "pre-shrunk" tees after five washes and tumble drying. Two lots shrink about 3% in length, but one shrinks 7%. The brand holds the claim, asks the supplier to fix finishing, and adds the claim only after three consecutive lots pass its internal limit.

Matching the claim to the care label

If the care label allows tumble drying, test with tumble drying. A claim that holds only after line drying, while the label says tumble dry low, invites complaints. Where tumble drying causes too much shrinkage, either change the label to line dry or improve the fabric finishing before using the claim.

Keeping evidence

File the test reports, the process description and the internal limit with the style records so the claim can be supported if a customer, retailer or authority asks.

Limits

No universal numeric limit defines "pre-shrunk"; check local rules and retailer requirements for your markets.

Facts, recommendations and uncertainty

Established: "pre-shrunk" implies limited further shrinkage and claims should be supported by evidence. Recommendation: test each lot with ISO 5077 and set an internal limit before using the claim. Uncertain: the exact threshold regulators or retailers in each market apply.

Sources and further reading

• ISO 5077:2007 — Determination of dimensional change in washing and drying
• ISO 6330:2021 — Domestic washing and drying procedures for textile testing
• ISO 3759:2011 — Preparation, marking and measuring of fabric specimens and garments for dimensional change

Standards and regulations are referenced by their published scope. Test parameters, cycles and pass levels should be agreed with your laboratory for the specific product; legal requirements should be confirmed for each destination market.