Probably both. But start by measuring, because the label must follow the evidence and not the other way round. If the fabric shrinks noticeably when washed and dried as the label says, the label is not doing its job. A gentler instruction may reduce the problem. If even gentle care still produces unacceptable shrinkage, the fix belongs in the fabric or its finishing.

Measure shrinkage under the labelled care

Dimensional change after home laundering is measured on garments by methods such as AATCC TM150, which AATCC revised in 2025 to align with its LP1 and LP2 laundering parameters, or by using a named procedure such as ISO 6330. Mark and measure the garment, wash and dry it under the conditions on your current label, then measure again. Repeat with the gentler care you are considering. That gives you the evidence for both the label decision and the fabric conversation.

What the label must do

In the United States, the FTC Care Labeling Rule (16 CFR Part 423) requires care labels on textile wearing apparel. It requires a reasonable basis for the instructions, and the label must warn about any procedure a consumer might expect to use that would harm the product. The FTC's business guide explains this in plain language. Outside the U.S., ISO 3758 defines the care symbols. It states that each symbol indicates the most severe treatment that does not cause irreversible damage.

So if warm washing and tumble drying cause the shrinkage your customers report, "machine wash warm, tumble dry" is not a supportable instruction for that fabric. Changing to "wash cold, tumble dry low" or "line dry" is only correct if your test under those conditions gives an acceptable result.

Fix the fabric where you can

Ask the factory what finishing the fabric received and what dimensional change it achieves under your test. Then set a shrinkage tolerance in the order, tested to a named method. A pajama that needs very restrictive care to keep its size may still disappoint customers who ignore the label. A more stable fabric reduces the reliance on the label.

In order: measure under current care, decide whether a gentler label is supported, then fix the fabric so the label does not have to carry the whole problem.