Two statements appear in the source
The selected UK product details display wash at 40°C delicate. Their embedded inline care reference also says machine washable even at 30º. That difference appears across the three selected records. It has not been resolved by inspecting a delivered garment, so this guide does not publish either number as a universal instruction.
Do not settle a version conflict by guesswork
Choosing the lower number because it sounds cautious would still be an unsupported instruction. The entries may have different context or version history; the public record does not explain it. A site calculation cannot determine the correct cycle for the garment actually supplied.
Keep country and selected style together
Do not resolve the issue with another country’s listing, even if the style code resembles the UK selection. Keep the exact UK colour, age label and SKU with the conflicting statements. A screenshot or saved source extract makes a customer-service query much more useful than an unspecific question about washing cotton.
Resolve the supplied label before use
Before laundering, read the current sewn care label and ask the seller to clarify any continuing difference. Follow confirmed instructions for the received garment. No shrinkage, colourfastness or wash-cycle trial was performed here, and the disagreement remains visible in the product finder and internal evidence record.
Apply it to the selected purchase
Save both the rendered 40°C delicate line and the embedded 30º reference with the exact SKU. That lets the seller investigate a source mismatch without guessing which garment you mean.
Sources & scope
Checked November 5, 2026. Manufacturer and retailer references support the specific statements. Dated displayed prices are not final checkout quotes, performance rankings or performance testing. This shopping reference does not replace the exact product label or retailer instructions. Current received labels and independent apparel/textile/content/commerce review remain pending.
M&S UK Powder Blue teeT874395B ↗
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