A new duty on employers to inform staff of their right to join a trade union in the UK is set to come into force from October 2026 as part of a raft of changes relating to trade unions being introduced under the Employment Rights Act 2025.

The new rules will require all employers to issue every worker a written statement setting out their rights to join a trade union. The written statement must be provided at the same time as the worker's written statement of particulars and at other prescribed times.

Many employers, particularly smaller businesses with no history of trade union involvement, may assume that because they do not recognise a union or have no union members, the issue does not affect them.

However, the duty applies regardless of whether a workplace is unionised and sits alongside wider reforms designed to make union recognition and organising easier (see box). With that in mind, employers should treat the obligation as part of a broader industrial relations strategy rather than a document update exercise.

Getting ready for implementation

The government is currently consulting on how the duty should be implemented in practice. However, failure to provide a statement will result in an uplift of between two to four weeks’ pay where another successful substantive claim, for example unfair dismissal and/or discrimination, is brought.

“The change is part of the Government’s objective to empower workers by ensuring they are fully informed of their rights to join a union. What we're saying to clients is that you need to be ready for an increase in union activity, even where it's not been relevant previously,” says Edward Arnold, Of Counsel in the CMS UK Employment team.

Employment law solicitor Bobby Ahmed, Managing Director of Neathouse Partners, says the biggest risk is likely to be employers overlooking the requirement altogether. “Businesses will need to review their onboarding processes, contracts, staff handbooks and induction materials to make sure the required information is provided.

“Once the final guidance is published, update recruitment and induction documents, make sure HR teams and managers understand the new requirement and keep a record that the information has been provided. Treat it in the same way as other statutory information that must be given to new starters,” Ahmed says.

For most businesses this should not be a complicated or costly change, but it is another reminder of the need to keep employment documentation under regular review, Ahmed says. “Small administrative duties can become legal issues if they are missed, particularly where there is a statutory obligation backed by enforcement powers.”

Why engagement matters

Given that the purpose of the new rules is to promote the value of collective bargaining and the employee collective voice, Arnold’s advice is to ensure you have proactive engagement with your workforce.

“Unions are likely to target disaffected workforces, therefore a proactive approach to engaging with staff may reduce interest in union membership. Many larger employers have existing employee representative groups, who they will talk to about significant workplace changes. If you have something like that, and it's effective, then unionisation may be less appealing.”

Potential stumbling blocks for employers

Other changes relating to trade unions

Right of trade unions to access workplaces

The ERB also introduces a new right of trade unions to access workplaces, both in terms of physical entry and digital access, to meet, support, represent, recruit or organise workers and to facilitate collective bargaining. Organising industrial action is expressly excluded. A draft Code of Practice was published in April. The changes relating to the new right of access are due to come into effect in October 2026.

Trade union recognition

Since April 2026, the ERA simplifies the existing statutory trade union recognition process. It allows for the support threshold for recognition to be reduced from the current 10% potentially down to as low as 2% (although the final percentage has yet to be set.) It also removes the requirement for a trade union to demonstrate that there is likely to be majority support for trade union recognition.

The ERA also removes the 40% support threshold from recognition ballots so that only a majority of those voting will be required. “It’s about giving workers a meaningful right to organise through trade unions. Effectively, it's brought the threshold down, so union recognition will be a lot easier,” Arnold says.

Time off and facilities for union representatives

From October 2027, the ERA will also allow union equality representatives to take paid time off during working hours for various union related activities. Employers must also provide them with reasonable access to facilities, such as meeting rooms and internet access, where requested by the employee.

Strengthened protection against blacklisting

Currently, employers are banned from ‘blacklisting’ trade union members for employment purposes. Additional protections against blacklisting are also due to come into effect in 2027.The ERA will prohibit third parties from compiling and supplying blacklists, not just employers and employment agencies including AI-generated or digital blacklists as employers becoming increasingly reliant on automated hiring platforms.