UKMy employer won't let me join a trade union. Is this legal?
No, it is illegal for your employer to stop you from joining a trade union in the UK. You have a statutory right to join any trade union of your choice.
What the Law Says
UK law explicitly protects your right to join a trade union and engage in union activities without interference from your employer.
Under the Employment Rights Act 1996 (ERA), it is unlawful for an employer to subject you to any detriment — such as denial of promotion, disciplinary action, or dismissal — because you are a member of a trade union, have taken part in union activities, or intend to do so.
This protection applies whether you’re joining a union for the first time, rejoining after a break, or participating in lawful union duties like attending meetings or representing colleagues.
The law also prohibits employers from offering inducements (e.g., extra pay or benefits) to persuade you to give up union membership or rights — this is known as 'union-busting' and is banned under section 145B of the ERA.
Statutory TextAn employee has the right not to be subjected to any detriment by any act, or any deliberate failure to act, by his employer done on the ground that the employee is a member of an independent trade union.
— Employment Rights Act 1996, s. 146 — Protection from detriment: trade union membership etc.
Statutory TextA worker has the right not to have an offer made to him by his employer which would, if accepted, result in him giving up, or refraining from, union membership or activities.
— Employment Rights Act 1996, s. 145B — Prohibition of offers to induce workers to give up union rights
What to Do
Tell your employer — in writing — that you are exercising your statutory right to join a trade union under section 146 of the Employment Rights Act 1996.
Keep records of all communications, including dates, names, and any adverse actions taken after you declared your intention to join.
If you suffer a detriment (e.g., being denied training, disciplined, or dismissed), file a claim with an Employment Tribunal using form ET1 within 3 months less one day of the incident.
You may seek free advice from Acas, your union, or a legal adviser before making a claim.
If dismissed solely for union membership or activity, this is automatically unfair dismissal — no minimum service period applies.
Sources
Same Question, Other Jurisdictions
Canada
European Union
US Federal
JapanNot legal advice. This article is general information based on publicly available sources, written for educational purposes. Laws change and individual situations vary. Consult a licensed attorney in your jurisdiction before acting on anything you read here. Last reviewed: 2026-06-08.