Can my employer change my contract?

The short answer

Your employer cannot change the main terms of your employment (pay, hours, duties, job title, location, benefits) on their own. Changes need your agreement, or your union's agreement if you are in a bargaining unit.
The Industrial Court has said many times that it is unlawful for an employer to change existing terms and conditions on its own.
Some changes may be allowed if your contract has a clear flexibility clause, or if the employer genuinely consulted and had a real business need. Policies in a handbook that are not part of your contract can usually be updated with notice.

You do not have to sign it. If you are pressured to sign, write "signed under protest" next to your signature.
Send a short email or letter to HR or management saying you do not agree to the changes and are continuing to work under protest. Keep a copy.
Keep your original contract, the addendum, emails and payslips from before and after the change.
Do not wait. Carrying on without objecting can be treated as accepting the new terms.

In a union: contact your union. It can raise the matter with the employer and report a trade dispute to the Minister of Labour, which can go to the Industrial Court.
Not in a union: the Ministry of Labour's Conciliation, Advisory and Advocacy Division can advise and try conciliation. To take a dispute to the Industrial Court you will usually need a registered trade union to represent you. See Your right to join a union.
If the change takes your pay below minimum wage or breaks leave or hours rules: the Ministry of Labour's Labour Inspectorate.
If the change targets you because of sex, race, religion, marital status or another protected ground: the Equal Opportunity Commission.
Senior managers outside the Industrial Relations Act: a breach of contract claim in the High Court, through an attorney.

If your employer seriously breaks your contract (for example, cuts your pay, demotes you, moves you without a right to, or makes your job untenable), you may resign and treat it as a dismissal. This is called constructive dismissal.
You must show a serious breach, that you resigned because of it, and that you did not delay too long.
Get advice from your union or an attorney BEFORE resigning. Resigning without advice can weaken your case.
Dismissal disputes must be reported within 6 months.

Last reviewed: October 2026

General guidance only, not legal advice.