UK REACH vs EU REACH: The Growing Divergence Creating a Double Compliance Burden

How UK REACH and EU REACH Diverged#

Before Brexit, the UK participated in EU REACH — the Registration, Evaluation, Authorisation and Restriction of Chemicals framework administered by the European Chemicals Agency (ECHA). After Brexit, the UK created its own REACH regime administered by the Health and Safety Executive (HSE). At the point of divergence, UK REACH inherited the EU's substance registrations and restriction list. Since then, the two regimes have been evolving independently. The EU has continued adding substances of very high concern (SVHCs) to the REACH candidate list — there are now over 240 — while the UK has proceeded at a slower pace. The two regimes now have different SVHC lists, different authorisation decisions for some substances, and are beginning to diverge on restriction timelines for certain chemicals.

The Double Registration Problem#

Under EU REACH, manufacturers and importers placing more than one tonne of a chemical substance on the EU market per year must register it with ECHA. Under UK REACH, the equivalent threshold triggers registration with HSE. A company manufacturing chemicals in the UK and exporting to the EU must register each relevant substance separately with both agencies — paying two sets of fees, maintaining two technical dossiers, and undergoing two evaluation processes. For larger portfolios, this duplication is extremely costly. ECHA registration fees alone can run to tens of thousands of pounds per substance for larger tonnage bands. The UK grandfathering provisions that allowed companies to rely on prior EU registrations expired in October 2023, meaning all UK registrations must now be fully UK-based.

Authorisation Lists and Substances of Very High Concern#

Substances of very high concern — those that are carcinogenic, mutagenic, reprotoxic (CMR), persistent bioaccumulative and toxic (PBT), or of equivalent concern — face the most stringent controls. In the EU, use of an SVHC on the authorisation list requires an explicit grant of authorisation from ECHA. In the UK, HSE administers equivalent controls. The two lists are now diverging: some substances appear on the EU candidate list but not yet on the UK list, and vice versa. Businesses operating in both markets must monitor two separate candidate lists and authorisation lists, assess which apply to their substances, and maintain separate authorisation applications where required. AskBiz tracks SVHC list updates across both regimes so your compliance team is not chasing two sets of regulatory announcements.

What This Costs Businesses Operating in Both Markets#

A 2023 estimate from the Chemical Industries Association suggested UK chemical exporters to the EU face compliance costs 40-60% higher than before Brexit, primarily due to REACH duplication. For a medium-sized chemical business with 20-30 registered substances in multiple tonnage bands, full dual registration and dossier maintenance can represent hundreds of thousands of pounds annually. Beyond registration costs, there is a significant staff time burden: regulatory affairs teams must track two sets of consultations, respond to two agencies' queries, and manage two compliance calendars. Smaller businesses without dedicated regulatory resource are hardest hit, often needing to outsource compliance activities that were previously shared across the UK-EU market.

Practical Steps for Businesses in Both Markets#

Businesses exporting chemicals into the EU should first audit their substance portfolio: identify every substance above the one-tonne threshold and check its status under both EU and UK REACH. For EU market access, confirm whether an Only Representative (OR) arrangement is in place — non-EU manufacturers can appoint an EU-based OR to handle EU REACH registrations on their behalf. Review the SVHC candidate lists for both regimes and flag any substances that may require authorisation in either market. Prioritise substances where the two regimes are actively diverging, as these carry the highest risk of compliance gaps opening unexpectedly. Build a dual-regime compliance calendar covering registration renewal deadlines, SVHC consultations, and restriction proposal timelines for both ECHA and HSE.

• Since Brexit, the UK and EU operate separate REACH chemical regulations.
• Businesses trading chemicals in both markets must register substances twice, maintain two sets of dossiers, and monitor two diverging lists of substances of very high concern (SVHCs).
• The duplication cost is substantial — and the two regimes are increasingly diverging on authorisation decisions and restriction timelines.