Your employer cannot unilaterally change your employment contract without your agreement. This guide explains when changes are lawful, what you can do if your employer imposes changes, and when you may have a constructive dismissal claim.
Your employment contract is a legally binding agreement. Your employer cannot simply rewrite it whenever they like — and if they try to force through changes you have not agreed to, you have real legal remedies.
This guide explains when contract changes are lawful, when they are not, and what you can do about it.
An employment contract, like any contract, can only be varied by agreement of both parties. Your employer cannot impose new terms unilaterally.
This applies regardless of whether the change affects pay, hours, location, duties, benefits, or any other term. The key question is always: did you agree to the change?
Many contracts include flexibility clauses — terms that expressly allow the employer to make certain changes. For example:
"The company reserves the right to change your place of work to any location within a 25-mile radius."
If the contract contains such a clause, your employer may be able to make the specified change without needing fresh agreement. However, these clauses must be exercised reasonably — they cannot be used to impose wholly unreasonable or unforeseeable changes.
If you agree to the change — expressly (in writing or verbally) or by conduct (by simply continuing to work under the new terms without objection for a significant period) — the variation becomes binding.
Be careful: if you continue working after a change without protesting, you may be taken to have accepted it by conduct. If you disagree, you must make your objection clear in writing.
If there is a trade union recognised by your employer and your contract incorporates a collective agreement, changes negotiated through that agreement may update your terms — depending on how your contract is drafted.
If your employer changes your contract without your agreement and without a contractual right to do so, that is a unilateral variation — and it is a breach of contract.
Common examples of unlawful unilateral changes:
You can write to your employer formally objecting to the change and stating that you are continuing to work "under protest" — meaning you are not accepting the new terms. This preserves your right to sue for breach of contract without resigning.
This approach is safest for lower-stakes changes (e.g. a small pay cut) where leaving immediately would harm you financially.
If the change is serious enough — and particularly if it goes to the heart of your contract (e.g. a significant pay cut, removal of major benefits, demotion) — you may be entitled to treat yourself as constructively dismissed.
Constructive dismissal occurs when your employer's fundamental breach of contract leaves you with no reasonable choice but to resign. You can then bring an unfair dismissal claim at tribunal.
You need 2 years' continuous service for a standard unfair dismissal claim. Exceptions apply for dismissals related to discrimination, whistleblowing, or the exercise of statutory rights.
This carries significant risk — your employer may treat your refusal as a disciplinary matter. It is generally not recommended unless you have strong legal advice supporting the position.
If the change involves an unlawful reduction in your pay, you can bring a wages deduction claim in the employment tribunal under Part II of the Employment Rights Act 1996. This is straightforward and has a 3-month time limit.
"Fire and rehire" (or "dismissal and re-engagement") is where an employer dismisses employees who refuse the new terms and immediately offers to re-engage them on the changed contract.
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