UK REACH Transitional Registration Deadlines Legally Extended to 2029–2031

UK REACH Registration Deadlines Are Now Confirmed in Law

On 22 December 2025, the Department for Environment, Food & Rural Affairs (Defra) published the government response to its consultation and selected the option of moving the three submission deadlines to 2029, 2030 and 2031. At that point, legislative amendments were still required. The 2026 Regulations have now completed that step and made the revised timetable legally effective.

UK REACH regulates the manufacture, import, supply and use of chemicals in Great Britain—England, Scotland and Wales. EU REACH continues to apply in Northern Ireland under the Windsor Framework. Companies should therefore distinguish their Great Britain and Northern Ireland supply chains when determining registration responsibilities.

Companies needing a broader overview of the framework can refer to the REACH24H UK REACH service page. Its deadlines section should be updated at the same time as this article so that both pages reflect the current statutory timetable.

New UK REACH Transitional Registration Deadlines

The submission phases continue to be determined by annual tonnage and hazard profile. The formal timetable also updates the Candidate List cut-off dates used to allocate substances to the first two phases.

Where a substance may meet more than one criterion, the registrant should determine the earliest applicable phase by reference to its tonnage, classification and Candidate List status. Tonnage and legal-entity coverage should be reassessed whenever supply arrangements change.

What Else Changes Under the 2026 Regulations?

Protected Transitional Imports Are Extended

The amendment to Article 127P also extends the period during which eligible GB downstream users and distributors that imported from the EU before the end of the EU Exit implementation period may continue to make protected transitional imports under Article 127E(2). This extension follows the same revised timetable.

A DUIN is not a UK REACH registration. A business relying on the DUIN arrangement must still complete the applicable registration if it intends to continue importing the substance after the relevant transitional deadline.

HSE Compliance-Check Timelines Are Realigned

Article 41(5) requires HSE to conduct compliance checks on at least 20% of registration dossiers. To ensure these checks take place after the corresponding information has been submitted, the statutory completion dates have been moved to:

• 27 October 2030 for the first registration phase;

• 27 October 2032 for the second registration phase; and

• 27 October 2036 for the final registration phase.

The Regulations Do Not Yet Implement the ATRm

The 2026 Regulations extend deadlines; they do not finalise or legislate the ATRm. The government is continuing to develop the alternative model, which is intended to reduce unnecessary duplication and the cost of accessing EU-held hazard data while maintaining protection for human health and the environment.

Until the ATRm requirements are formally adopted, companies should not assume what the final data package will contain. Current UK REACH obligations remain applicable, and businesses should continue monitoring Defra and HSE updates before making major data-purchasing or dossier decisions.

What the Extension Means for Chemical Companies

The revised timetable provides more time for businesses to plan registrations, coordinate data access and spread project costs. It may also reduce the risk of rushed dossiers and unnecessary expenditure on data that could be treated differently under the future ATRm.

However, the extension is a deferral—not an exemption. Transitional registrants that intend to continue manufacturing or importing at or above the relevant tonnage threshold must still prepare to meet the applicable deadline. High-tonnage substances, CMRs, substances very toxic to aquatic organisms and Candidate List SVHCs remain in the earliest phase.

The deadline extension also does not suspend ongoing duties relating to supply chain communication, safety data sheets, classification and labelling, authorisation, restriction or other applicable UK chemicals legislation.

Recommended Actions for Registrants and Supply Chains

1. Confirm the applicable transitional route. Determine whether each substance is covered through grandfathering, a DUIN-supported import arrangement or another UK REACH registration pathway.

2. Remap substances against the new timetable. Review annual tonnage, hazard classification and Candidate List status using the 2027 and 2028 cut-off dates.

3. Maintain a proportionate data-gap plan. Continue organising substance identity, uses, tonnage, classification and available hazard information while avoiding unsupported assumptions about the final ATRm requirements.

4. Coordinate across the supply chain. Confirm the responsibilities of GB manufacturers, importers, Only Representatives, downstream users and data-sharing participants, including who will hold and maintain the registration.

5. Review commercial continuity. Identify substances that are critical to the GB market and assess the potential impact of supplier changes, tonnage growth or registration strategy decisions.

6. Monitor ATRm legislation and HSE guidance. Update registration budgets and project plans when the final information requirements and implementation arrangements are confirmed.

How REACH24H Can Help

REACH24H supports companies in assessing and preparing for UK REACH obligations, including:

• transitional-status and registration-pathway assessment;

• substance, tonnage and hazard mapping;

• UK Only Representative and importer coordination;

• data-gap review and dossier strategy;

• inquiry, registration and dossier preparation support; and

• ongoing monitoring of UK REACH and ATRm developments.

For assistance with UK REACH planning, companies may contact REACH24H to discuss their substance portfolio, supply chain structure and registration readiness.

Recommended Reading

• UK REACH Service

• Proposed Extension of the UK-REACH Transitional Registration Submission Deadlines

• 2026 Chemical Regulatory Outlook for Europe, the US, and Emerging Markets

Official Resources

• The REACH (Amendment) (No. 2) Regulations 2026

• HSE: Recognising EU REACH Registrations under UK REACH (Grandfathering)

• HSE: Downstream User Import Notification (DUIN)

• Defra: Summary of Consultation Responses and Government Response