Promissory Estoppel

Promissory estoppel is a legal principle that allows a party to enforce a promise made by another party even if there was no formal agreement or contract between them. It is often used in situations where there is no formal contract, but one party makes a promise to another party, and the other party relies on that promise to their detriment. To establish promissory estoppel, the following elements must be present:
  1. Legal relationship: There exists some form of legal relationship. A contractual relationship is the most common type of legal relationship. Parties to pre-contractual negotiations also fall within this principle.
  2. Promise: One party makes a clear and unambiguous promise that leads the other party to assume that the promise will be performed.
  3. Reliance: The other party relies on the promise and is induced to act.
  4. Detriment: The party relying on the promise suffers a detriment for having relied on the promise.
  5. Unconscionability: It would be unfair or inequitable to the other party if the party making the promise does not keep his promise.

If all of these elements are present, the party who made the promise may be estopped or prevented from going back on their promise, and the other party may be entitled to a remedy, such as damages or specific performance.

For example, your supplier promises to sell goods to you but asks you to arrange the delivery yourself. Because of his promise, you pay someone to take the goods to you. However, he later goes back on his promise and decides not to sell the goods to you. As you have relied on his promise and paid someone to do the delivery, you are now less well off and hence suffer a detriment. To avoid injustice, the supplier must keep his promise and sell you the goods. Alternatively, he needs to pay for the delivery as a remedy. The following is the analysis of this example using the above framework.
  1. Legal relationship: You are dealing with your supplier.
  2. Promise: Your supplier promises to sell you goods but asks you to arrange delivery.
  3. Reliance: You rely on his promise and pay someone to do the delivery.
  4. Detriment: After paying someone to do the delivery, you are now less well off.
  5. Unconscionability: It would be unfair or inequitable to you if the supplier refuses to sell you the goods unless he pays you the cost of delivery.
Back to blog
UOL Case Bank

UOL Case Bank

Upon joining, you become a valuable UOL student and gain instant access to over 2,100 case summaries. UOL Case Bank is constantly expanding. Speed up your revision with us now.

Subscribe Now

Where are our students from?

Yale University
Council of Europe
Baker Mckenzie 
University of Chicago
Columbia University
New York University
University of Michigan 
INSEAD
University College London (UCL)
London School of Economics (LSE)
King’s College London (KCL)
University of London
University of Manchester
University of Zurich
University of York
Brandeis University
University of Exeter
University of Sheffield
Boston University
University of Washington
University of Leeds
University of Law
Royal Holloway, University of London 
Birkbeck, University of London
SOAS, University of London
University of Kent
University of Hull
Queen’s University Belfast
Toronto Metropolitan University
Hong Kong University of Science and Technology
University of Buckingham

  • Criminal Practice

    Diagrams and Charts

    Our carefully designed diagrams and charts will guide you through complex legal issues.

  • Criminal Law

    Clear and Succinct Definitions

    Key concepts are concisely defined to help you understand legal topics quickly.

  • Property Law

    Statutory Provisions

    Statutory provisions are provided side by side with legal concepts to help you swiftly locate the relevant legislation.

  • Public Law

    Case Summaries

    We have summarised important cases for you so that you don't need to read long and boring cases.

  • Evidence

    Rules and Exceptions

    Rules and exceptions are clearly listed so that you know when a rule applies and when it doesn't.

  • Company Law

    Terminology

    Legal terms and key concepts are explained at the beginning of each chapter to help you learn efficiently.

  • Case Law

    Case law is provided side by side with legal concepts so that you know how legal principles and precedents were established.

  • Law Exam Guide

    Law Essay Guide

    You will learn essential law exam skills and essay writing techniques that are not taught in class.

  • Law Exam Guide

    Problem Question Guide

    We will show you how to answer problem questions step by step to achieve first-class results.

  • Conflict of Laws

    Structured Explanations

    Complex legal concepts are broken down into concise and digestible bullet point explanations.

  • Legal System and Method

    Legal Research

    You will learn legal research techniques with our study guide and become a proficient legal researcher.

  • Jurisprudence and Legal Theory

    Exam-focused

    All essential concepts, principles, and case law are included so that you can answer exam questions quickly.