UK REACH ATRm REGULATORY UPDATE
On 29 September 2026, the UK Department for Environment, Food & Rural Affairs (Defra) opened a six-week technical consultation on draft provisions for the Alternative Transitional Registration model, or ATRm, under UK REACH. The consultation document is dated 29 September 2026, and the consultation closes on 10 November 2026.
The draft provisions would introduce streamlined information requirements for eligible transitional registrations while giving the Health and Safety Executive (HSE) new powers to request additional information when needed. Defra is seeking comments on whether the proposed legal text accurately reflects the intended policy, including any drafting issues, omissions, ambiguities or unintended consequences.
Regulatory Status
If implemented as proposed, the ATRm could materially reduce the upfront data burden and associated costs for some transitional registrants. However, the proposals remain subject to consultation and final legislation. Companies should not assume that UK REACH registration, data-sharing or risk-management responsibilities have been removed.
Quick Navigation
Jump to the key sections of this article.
Why Is the UK Introducing the ATRm
Following Brexit, substances previously registered under EU REACH may need to complete a separate transitional registration under UK REACH to remain on the Great Britain market.
The UK Government previously estimated that purchasing or obtaining access to EU hazard data for these registrations could generate approximately GBP 2 billion in one-off industry costs by 2030. The ATRm was therefore developed to avoid unnecessary duplication while maintaining a high level of protection for human health and the environment.
In its March 2026 response to the earlier ATRm consultation, the government confirmed that transitional registrants would submit less hazard information upfront. Regulators would instead be able to request supporting information where necessary.
The latest technical consultation is intended to translate that policy into legal provisions. It should be distinguished from the separate legislation that extended the UK REACH transitional registration deadlines to 27 October 2029, 27 October 2030 and 27 October 2031. The deadline legislation determines when transitional registrations must be completed, while the ATRm is expected to determine what information eligible registrants must submit.
For further information on the legally confirmed timetable, see our analysis of the UK REACH transitional registration deadlines.
Which Registrations Could Follow the ATRm Route
The streamlined requirements are intended to apply to eligible registrations of transitional substances. Under the proposed Article 127ZA definition, these are substances whose EU REACH registrations were in force immediately before 11pm on 31 December 2020. Relevant routes include:
Grandfathered registrations: transferred UK REACH registrations that meet the applicable transitional conditions.
New Registrations of Existing Substances (NRES): registrations for substances entering or re-entering the Great Britain market after the end of the transition period.
Registrations following a DUIN: registrations by qualifying downstream users or distributors that imported under the protected transitional arrangements after submitting a Downstream User Import Notification.
Isolated intermediates: qualifying existing or new registrations for on-site and transported isolated intermediates.
Eligibility would depend on the substance's regulatory history and the applicable route, rather than the size or type of the registrant. For the principal reduced-information routes under proposed Articles 127B and 127NA, the substance must remain registered under EU REACH as a non-intermediate at the same or a higher tonnage band. As an alternative for a Great Britain registration in the 1 to 10 tonnes per year band, the substance may qualify where it is registered under EU REACH as a transported isolated intermediate at 1,000 tonnes or more per year. Separate eligibility tests would apply to isolated-intermediate routes.
A substance that does not meet the applicable transitional conditions may remain subject to the standard UK REACH information requirements under Annexes VII-X. New substances entering the market after the transition period are not expected to qualify for the reduced transitional requirements.
Companies that are uncertain about their route can use a UK REACH registration assessment to review their substance history, legal entity, annual tonnage, importer structure and historical supply chain.
What Information Would Transitional Registrants Submit
Where the proposed reduced route applies, eligible registrants would submit a defined information package instead of the full set of study summaries, robust study summaries and testing proposals normally required for a standard registration. If the relevant eligibility conditions are not met, the standard Article 10 information requirements would continue to apply.
The proposed reduced package would focus on the following information.
Classification and Labelling
Registrants would submit the classification and labelling of the substance. Where there is no mandatory classification under GB CLP, the classification would need to be accompanied by a statement confirming consistency with the applicable harmonised classification in Annex VI to EU CLP or, if none exists, with the classification submitted by the EU REACH lead registrant and published by ECHA. Any inconsistency, or inability to provide a classification, would need to be explained.
Guidance on Safe Use
The reduced package would continue to include the guidance on safe use required by Article 10(a)(v), together with any relevant assessor indications.
Use and Exposure Information
The ATRm would retain the existing UK REACH requirements for information on manufacture and identified uses under Article 10(a)(iii). For substances registered at 1 to 10 tonnes per year, the exposure information required by Article 10(a)(x) and section 6 of Annex VI would also be submitted where relevant.
The government has decided not to proceed with the additional Great Britain-specific use and exposure information proposed during the 2024 consultation. This change is intended to avoid creating a further information-gathering burden for registrants and their supply chains.
Chemical Safety Assessment and Report Requirements
For substances manufactured or imported at 10 tonnes or more per registrant per year, Article 14(1) generally requires a chemical safety assessment and a Chemical Safety Report. Under the reduced route, the proposed provisions specify the assessment information that must be submitted and streamline how certain assessment steps are documented.
The required information would include relevant human-health, physicochemical and environmental hazard classifications; Derived No-Effect Levels (DNELs), Derived Minimal Effect Levels (DMELs) and Predicted No-Effect Concentrations (PNECs), as applicable; and the conclusions of the persistent, bioaccumulative and toxic (PBT) and very persistent and very bioaccumulative (vPvB) assessment. Registrants would need to confirm consistency with corresponding results submitted by the EU REACH lead registrant and published by ECHA, or explain any inconsistency or why a value could not be derived or provided.
Where Article 14(4) applies because the substance meets the specified hazard criteria or is assessed as PBT or vPvB, the submission would also include an exposure assessment, exposure scenarios and risk characterisation, together with specified physicochemical and ready-biodegradability information from Annex VII.
Substance Groups and Joint Submission
Proposed Article 25A would require relevant registrants and potential registrants of the same substance to participate in a Substance Group. The group would provide the forum for exchanging information and seeking agreement on classification and labelling. Depending on the route and information requirement, participants may also need to share study information, guidance on safe use, chemical safety information or information requested through transitional evaluation, while the existing joint-submission rules would continue to allocate information between lead and individual submissions.
Although the ATRm may reduce the amount of hazard data submitted upfront, it should not be interpreted as a zero-data registration route. Registrants would remain responsible for the accuracy of their hazard conclusions, the lawful use of supporting information and the management of data-sharing or cost-sharing arrangements where applicable.
Fees for Outstanding Transitional Information
The draft provides that no fee would be payable for submitting specified outstanding information for transferred Great Britain registrations and existing isolated-intermediate registrations under the proposed transitional arrangements. This proposed exemption would not remove other registration, data-sharing or compliance costs that may apply.
HSE Would Gain Transitional Evaluation Powers
To balance the reduced upfront information requirements, the proposed Articles 127Q-127U would give HSE a new transitional evaluation mechanism.
Where HSE considers further information necessary to evaluate the potential hazards or risks of a substance or intermediate, it could require one or more registrants to provide information that would ordinarily be required under Articles 10, 12, 17 or 18 but has not previously been submitted to HSE, even if the information was already provided to ECHA under EU REACH. Cases that may receive particular attention include:
registrations in which classification information or information on isolated intermediates is submitted separately;
substances included in the UK rolling action plan; and
substances that may meet the criteria for substance evaluation.
HSE would issue a draft decision identifying the information required and setting reasonable submission deadlines. Affected registrants would have 30 days from notification to comment before HSE makes and notifies a final decision. If a request concerns study summaries, robust study summaries or testing proposals, HSE could also require a further chemical safety assessment to the extent needed and require the relevant steps to be documented in the Chemical Safety Report.
After the requested information is submitted, HSE would examine it and could issue a further decision where necessary. Under proposed Article 127T, HSE would be required to complete the evaluation within 12 months of submission of the requested information; registrants would retain the right to appeal a transitional evaluation decision under the existing UK REACH appeal process.
If a registrant ceases manufacture or import before or after receiving a draft transitional evaluation decision, it would be required to notify HSE. Once notified, the registered volume would be reduced to zero and HSE could not request further information from that registrant under this mechanism. The power could apply again if manufacture or import later recommences.
The broader reforms discussed during the 2024 consultation - including changes relating to reporting, restrictions and animal testing - are not being implemented through the current ATRm package. They may instead be addressed through a wider programme of UK REACH reform.
What Should Companies Do Before the Rules Are Finalised
Businesses involved in the manufacture or import of chemicals into Great Britain should use the consultation and implementation period to clarify their registration position rather than waiting for the first transitional deadline.
Priority actions include:
Confirm the route: determine whether each substance qualifies for grandfathering, DUIN, NRES, an isolated-intermediate route or a standard new registration.
Check tonnage and timing: confirm the relevant annual tonnage band and the applicable 2029-2031 deadline.
Verify transitional evidence: review evidence of pre-2021 EU REACH registration and historical supply-chain relationships.
Review data readiness: assess the availability and quality of classification, use, exposure, DNEL, DMEL, PNEC and PBT/vPvB information, including the basis for any difference from the relevant EU information.
Plan data sharing: identify potential data rights, Substance Group and joint-submission issues.
Confirm the responsible entity: decide whether registration will be held by a Great Britain-based importer or an Only Representative.
Monitor implementation: follow the final legislation and HSE guidance before making irreversible data-purchasing or dossier decisions.
Reduced initial requirements may lower some project costs, but the actual impact will depend on the substance, tonnage band, hazard profile, available information, data rights and whether HSE later requests additional evidence.
How REACH24H Can Support UK REACH Registration
REACH24H supports overseas manufacturers, formulators, article producers and Great Britain-based importers with UK REACH registration planning and implementation.
Our support includes:
Route assessment: assessing UK REACH applicability, transitional eligibility and the appropriate registration route.
Only Representative support: providing Great Britain-based Only Representative support for eligible overseas suppliers.
Dossier preparation: reviewing grandfathering and DUIN evidence and preparing Article 26 inquiry or registration dossiers in IUCLID.
Data and maintenance support: supporting data-gap analysis, data-sharing strategy, joint submission and post-registration maintenance.
Companies preparing for the 2029-2031 transitional deadlines should begin by confirming their substance portfolio, responsible legal entities, importer coverage, tonnage allocation and available data.
Prepare Your UK REACH Registration Route for the ATRm
Confirm whether your substances fall under grandfathering, DUIN, NRES or an isolated-intermediate route, then review tonnage, data and legal-entity responsibilities before the 2029-2031 deadlines.
