Promissory Estoppel

What is Promissory Estoppel in Contract Law?

Quick Definition

Promissory estoppel is an equitable doctrine that prevents a party from going back on a clear promise, even where there is no consideration to support it. It is used to avoid unfairness where one party has relied on a promise to their detriment. It does not create a new cause of action but acts as a shield against strict legal rights.

In Context

Promissory estoppel typically arises in situations where a creditor agrees to accept reduced payments but later tries to claim the full amount. In Central London Property Trust v High Trees House Ltd, rent was reduced during wartime, and the landlord was prevented from claiming full rent for that period due to reliance on the promise. The doctrine requires a clear and unequivocal promise, reliance by the other party, and it must be inequitable to allow the promisor to go back on their word. However, it is generally suspensory, meaning it pauses rights rather than permanently extinguishing them. Courts use it cautiously to balance fairness with the need for certainty in contract law.

See Also

• Consideration

• Variation of Contract

• Estoppel

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