Warranty and Defect Returns: How to Write Them into a Factory Contract

A verbal agreement that "we'll sort it out if something's wrong" is worthless once the batch is paid for and defects are found. Here's exactly what to write into a factory contract on warranty and defects, so a claim carries formal weight instead of turning into endless negotiations with no result.

Acceptable defect rate — a specific number, not vague language

Instead of vague language like "good quality," the contract should state a specific acceptable defect rate, usually tied to the AQL (Acceptable Quality Level) standard — for example, AQL 2.5 for most non-food goods. Explicitly state that exceeding this rate in the agreed sample gives you the right to consider the entire batch as failing inspection, not just the specific defective units found.

Who pays for rework and re-sorting

State directly that the costs of re-sorting, rework, or replacement when the agreed defect rate is exceeded are borne by the factory, including any resulting shipping delays. Without this clause, a factory might formally acknowledge the defects but shift all remediation costs onto you, which effectively nullifies the point of the warranty.

Claim deadlines

Specify a concrete number of days after receiving the goods during which you have the right to file a claim for hidden defects not detectable during normal receiving inspection — usually 30-90 days depending on the product category. Also specify a deadline for the factory's response to such a claim, otherwise the process can drag on indefinitely with no consequence for the supplier.

How to document evidence for a claim

The contract should require photo and video documentation of the defect, showing the batch number and date, as a mandatory condition for the claim to be considered — this protects both sides from unsubstantiated accusations. It's useful to agree on the format of this documentation with the factory in advance, rather than arguing about it during an actual conflict, when both sides are less inclined to compromise.

Compensation — not just product replacement

Replacing defective units isn't the only compensation option: the contract can provide for a partial refund, a discount on the next order, or compensation for extra logistics costs if a defect-related delay caused you to miss deadlines with your own clients. The more specifically compensation options are spelled out in advance, the less room there is for the factory to drag out negotiations after the fact.

Why this is worth writing down even with a long-standing, reliable supplier

A good relationship with the factory lowers the odds of a dispute, but doesn't rule out a change of manager on the supplier's side, a change in business ownership, or a plain mistake on a specific batch. Formal contract terms aren't a sign of distrust — they're standard practice that most established Chinese factories treat as normal and don't take as an insult.