How to Amend an Existing Contract
Amend a contract by drafting a deed of variation or amendment letter that references the original agreement, clearly states the changes, and is signed by both parties. Ensure the amendment is supported by consideration or executed as a deed.
Last updated: February 2025
Step-by-Step Guide
Check the variation clause in the original contract
Most contracts specify how amendments must be made, often requiring written agreement signed by both parties.
- •Some contracts require amendments to be by deed, not just a signed letter.
Draft the amendment document
Write a variation agreement that references the original contract, lists each clause being changed, and states the new wording.
- •Use clear language like 'Clause X is deleted and replaced with the following'.
Ensure valid consideration
Under English law, a variation must be supported by fresh consideration from both parties unless it is executed as a deed.
- •Mutual promises to vary obligations typically provide sufficient consideration.
Execute and file the amendment
Both parties sign the amendment, and each retains a copy attached to the original contract for reference.
- •Date the amendment clearly and keep a master version of the contract with all amendments noted.
Legal Requirements
Under English common law, contract variations must be supported by consideration from both parties unless executed as a deed. The case of MWB Business Exchange Centres v Rock Advertising [2018] UKSC 24 confirmed that 'no oral modification' clauses are generally enforceable.
Common Mistakes
Template / Example
When to Get a Solicitor
If the variation is complex, involves a significant change in risk allocation, or if the original contract requires the amendment to be executed as a deed.
FAQ
Can I amend a contract by email?
It depends on the contract's variation clause. Some contracts accept written agreement by email, while others require formal signed documents or deeds.
Does a contract amendment need to be witnessed?
Not usually, unless the amendment is executed as a deed, in which case it must be signed and witnessed or executed under a company seal.
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