What is Notice of Defect?

The duty to notify defects — sometimes called the complaints obligation — is a standard requirement of commercial contract law. The underlying principle is straightforward but unforgiving: a buyer who discovers a defect must notify the supplier within a reasonable time. Failure to do so results in the loss of all legal rights in relation to that defect.

The precise meaning of "reasonable time" depends on the circumstances and the applicable law. In consumer transactions, many jurisdictions protect buyers by treating notifications made within two months of discovery as automatically timely. In B2B transactions, the standard is stricter: notification within a matter of weeks is typically required.

Many contracts and general terms of sale specify a contractual notification period: for example, five or eight working days after receipt for visible defects, or fourteen days after discovery for hidden defects. In B2B relationships, shorter periods than the statutory default can be validly agreed. It is therefore critical to check the defect notification period in the supplier's terms before signing.

A defect notice must be sufficiently specific to be effective. The buyer should describe what the defect is, when it was discovered, and what remedy they are claiming — repair, replacement, or damages. A vague complaint such as "it is not working properly" may not qualify as a legally effective notice.

In practice, the notification deadline is frequently missed. Businesses discover a defect, discuss it internally, and submit a formal complaint weeks later. If the contractual or statutory period has already expired, the supplier has a strong defence and the buyer's claim may be lost entirely.

The duty to notify defects is one of the most underestimated pitfalls in commercial law. A serious and entirely attributable failure can become unenforceable simply because the affected party did not notify the supplier promptly enough. This applies equally to professional parties in B2B relationships.

For SMBs, the practical message is simple: as soon as you identify a defect, act immediately. Notify the supplier in writing, describe the defect specifically, and keep proof that the notification was delivered. Acting one day late can be the difference between an enforceable claim and a lost right.