29/09/2026
Can your employer stop you joining a trade union?
In most cases, no.
Joining a trade union is your choice — and your employer generally cannot stop you from joining, pressure you to leave, threaten you because of your membership, or treat you unfairly for taking part in lawful union activities.
You also have important legal protections against dismissal or other workplace detriment because of trade union membership or activities.
So what should you do if things change after you join?
Keep records of emails, messages and conversations.
Note any changes in how you are treated.
Speak to your trade union for advice.
Consider raising a formal grievance if the issue is not resolved.
Trade unions can provide workers with collective representation, advice and support on issues including pay, working conditions, disciplinary proceedings and grievances.
The bottom line: your decision to join a trade union is yours — not your employer’s.
If you believe you have been treated differently because of your union membership, don't simply brush it off. Know your rights, keep evidence and get advice.
https://castleassociates.org.uk/blog/can-my-employer-stop-me-joining-a-trade-union