Stilk v Myrick is a well-known English contract law case decided in 1809 by the Court of King’s Bench.

In this case, the plaintiff, Stilk, was a seaman who had signed a contract to work aboard a ship. The contract stated that he would receive a certain amount of wages for the entire voyage. During the voyage, two of Stilk’s fellow seamen deserted the ship, leaving the remaining seamen with additional work to do. The captain promised to divide the wages that had been allocated to the deserters among the remaining seamen. However, when the ship returned to port, the captain refused to do so.

Stilk sued the captain for the additional wages, arguing that the captain had promised to pay them. The court, however, held that the captain was not obliged to pay the additional wages as there was no consideration for the promise. The court stated that the remaining seamen were already contractually bound to perform their duties, and that they were not providing any new consideration in return for the captain’s promise. Therefore, the promise was not binding.

The decision in Stilk v Myrick established the principle that performing an existing contractual duty is not sufficient consideration for a contract variation. This principle is known as the rule in Stilk v Myrick. However, the decision has been subject to criticism, and subsequent cases have recognised various exceptions to the rule, such as the case of Williams v Roffey Bros & Nicholls Contractors Ltd [1990].