Since 1 January 2024, the body of EU-derived employment rules that survived Brexit has been reclassified as “assimilated law.” EU supremacy and the general principles of EU law no longer apply to these provisions. Post-Brexit rulings from the Court of Justice of the European Union do not bind UK courts. For employers and HR teams, familiar rules now sit on shifting ground, subject to reinterpretation by domestic courts and to amendment through ordinary legislation such as the Employment Rights Act.
Assimilated law and UK court divergence from EU precedent
The distinction between “retained EU law” and “assimilated law” is not merely taxonomic. Earlier EU case law can still bind lower UK courts, but only until a higher domestic court decides otherwise. That creates a period of legal uncertainty around provisions employers have relied on for years, from working-time limits to TUPE protections.
Further reading: 2026 changes to UK immigration law: How they affect your workforce
A telling example is working-time recording. The EU Court of Justice ruled in 2019, in CCOO v Deutsche Bank, that EU member states must ensure a reliable system for measuring each worker’s daily working time. Great Britain is not bound by that post-Brexit ruling and has no equivalent general obligation to record every worker’s daily hours. Employers operating across the Channel now face divergent compliance expectations on the same underlying subject.
This divergence will deepen. The government’s special post-Brexit reform process reached a milestone by reclassifying surviving rules, but assimilated law can still be amended through other domestic legislation. Nothing about the current settlement is permanent, and treating EU-derived provisions as frozen would be a mistake.
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Employment Rights Act 2026: where Brexit gaps meet domestic reform
The Employment Rights Act (formerly the Employment Rights Bill) represents the most extensive overhaul of employment law in England, Scotland and Wales in a generation. Its scope overlaps directly with areas previously governed by EU-derived rules, which makes the interaction between the two frameworks worth examining closely.
Day-one protections and the end of qualifying periods
Under the new Act, unfair dismissal protection applies from the first day of employment. This is a domestic policy choice, not an EU requirement, but it fills a gap that EU membership never addressed. The EU framework set floors for certain rights (holiday, parental leave, non-discrimination) without mandating day-one unfair dismissal protection.
Employers who previously relied on a qualifying period before unfair dismissal claims could be brought now need to restructure probation processes. The Act introduces a lighter-touch statutory probation period, but the details of how tribunals will handle early-stage dismissals remain to be tested.
Sick pay and parental leave changes
Reforms to statutory sick pay remove the waiting period and lower earnings threshold, bringing more workers into scope. Parental and paternity leave become day-one rights, removing the previous qualifying service requirement. These changes extend protections beyond what the EU-derived baseline required, but they also replace provisions whose legal footing was partly European.
For payroll teams, the practical burden is significant. Systems built around the old qualifying thresholds need updating, and the interaction between new sick pay rules and existing contractual schemes requires review.
Trade union rights and collective bargaining after Brexit
One area where Brexit and the Employment Rights Act intersect in a less obvious way is collective labour relations. EU law set minimum standards for information and consultation but left trade union recognition largely to national systems. The new Act strengthens trade union access rights and simplifies the recognition process.
- Employers must now allow union representatives reasonable access to workplaces for recruitment and organising purposes, a right that goes well beyond previous UK or EU requirements.
- The thresholds for statutory union recognition ballots have been revised, making it easier for unions to secure recognition in workplaces where membership has been growing.
- Industrial action ballot requirements have been relaxed, with shorter notice periods and longer mandate windows, reversing restrictions that predated Brexit but were never constrained by EU law.
These reforms are entirely domestic in origin. Brexit removed the EU floor without removing the political pressure to expand worker protections. The government has used the legislative space to go further than the EU framework ever required in this area.
Harassment, equality, and the limits of current data
The Employment Rights Act introduces a strengthened duty on employers to take reasonable steps to prevent sexual harassment, including by third parties. Separately, provisions around gender pay gap reporting and menopause support are being phased in across 2026 and 2027.
Where the picture becomes less clear is enforcement. The Fair Work Agency is expected to consolidate enforcement functions currently spread across multiple bodies, but the timelines for its full operation and the resources it will receive have not been confirmed in detail. Whether enforcement capacity will match the expanded scope of employer duties is an open question.
The Equality Act 2010 was domestic legislation even before Brexit, so EU withdrawal does not directly weaken it. The risk lies elsewhere: in the loss of the interpretive influence of EU equality directives and CJEU case law that UK tribunals drew on for decades.
As higher courts begin to depart from that case law, the practical meaning of provisions around indirect discrimination, reasonable adjustments, and equal pay may shift in ways that are difficult to predict from the statutory text alone.
What employers operating across the UK and EU should track
For businesses with operations or workers on both sides of the Channel, the compliance landscape has become genuinely bifurcated. A few areas deserve particular attention.
- Working-time recording obligations differ: the EU requires systematic tracking following CCOO v Deutsche Bank, while the UK does not. Employers applying a single policy across jurisdictions need to decide which standard to follow.
- The UK-EU Trade and Cooperation Agreement includes a non-regression clause on labour standards, but its enforcement mechanism has not been tested in practice. Whether it would constrain future UK deregulation remains uncertain.
- Cross-border worker mobility is governed by the TCA and the UK’s points-based immigration system, not by free movement. Employers sponsoring EU nationals face administrative requirements that did not exist before 2021.
- Northern Ireland follows a separate employment law reform path, adding another layer for employers operating across the UK.
The legislative calendar for 2026 and 2027 is dense. Several provisions of the Employment Rights Act take effect in phases, with secondary legislation and codes of practice still being finalised. Employers who wait for final guidance before acting risk falling behind on contract updates, policy revisions, and payroll system changes that cannot be implemented overnight.
