UK REACH ATRm: Draft Legislation published – reduced upfront requirements, but what happens later?

On 29 September 2026, Defra published draft legislative provisions intended to implement the Alternative Transitional Registration Model (ATRm) for UK REACH. Presented through a Keeling Schedule and supporting amendment documents, the proposals form the basis of a six-week technical consultation that closes on 10 November 2026. The consultation seeks comments on the draft legal provisions before the legislation is finalised.

The Government published its ATRm policy conclusions in March 2026. The current consultation is therefore focused primarily on whether the proposed legislation gives effect to those conclusions clearly and works as intended in practice.

At first glance, the proposals appear positive for industry. They reduce the volume of information that certain transitional registrants would need to submit upfront and are intended to provide a more proportionate registration framework while maintaining protection for human health and the environment.

However, the consultation raises a broader question:

 

Does ATRm reduce the overall regulatory burden, or does it change when and how information may need to be provided?

Our initial review suggests businesses should look beyond the volume of information required at the point of registration and consider how the proposed framework could operate across the full lifecycle of a registration.

 

What does the draft legislation actually do?

The draft legislation proposes a new model for transitional UK REACH registrations.

In broad terms, it would:

  • allow certain registrants to use alternative information requirements where specified conditions are met;
  • link those requirements in part to the existence and status of corresponding EU REACH registrations;
  • require participation in substance groups for registrants and prospective registrants of the same substance;
  • maintain joint-submission and data-sharing mechanisms;
  • introduce a new transitional evaluation process; and
  • allow HSE to request additional information where this is considered necessary to evaluate potential hazards and risks.

Importantly, not every transitional registration would automatically be subject to the alternative information requirements. Which requirements apply depends on specified conditions, including the status of the corresponding EU REACH registration and, in some circumstances, the relevant tonnage band.

The proposals also create obligations that extend beyond the initial registration process. Depending on their circumstances, businesses may need to:

  • participate in substance groups;
  • exchange specified information with other registrants;
  • address differences in classification and labelling;
  • justify departures from relevant EU classification information;
  • support joint-submission and data-sharing arrangements; and
  • respond to requests for further information through transitional evaluation.

ATRm should therefore not be considered solely in terms of the amount of information submitted initially. Its practical implications will also depend on how these mechanisms operate after registration.

 

Reduced upfront requirements, but greater importance of subsequent evaluation

Much of the discussion around ATRm has focused on reducing the information that certain transitional registrants would need to submit routinely.

For many businesses, this is one of the most significant potential benefits of the model.

However, the draft legislation also establishes a transitional evaluation process under which HSE could request further information where it considers this necessary to evaluate the potential hazards and risks of a substance.

That information may include material that was not initially submitted to HSE and, in some circumstances, information previously provided to ECHA under EU REACH.

This means businesses should not assess ATRm solely on the basis of what they may no longer need to submit at the transitional registration stage.

An equally important question is:

 

What information no longer needs to be submitted upfront, and what information could HSE subsequently request?

For registrants, this places greater importance on understanding not only their initial submission requirements but also their ability to respond if further evidence is required later.

 

Substance groups could become an important part of implementation

One of the more significant structural changes in the proposals is the introduction of substance groups.

Proposed Article 25A would require relevant registrants and potential registrants manufacturing or importing, or intending to manufacture or import, the same substance to participate in a substance group. The aims include facilitating the exchange of specified information and agreeing classification and labelling where participants differ.

The policy logic is clear: substance groups are intended to support information exchange and address differences between registrants.

How efficiently those arrangements operate in practice will depend on how participants manage cooperation, costs, confidentiality and disagreement.

Practical questions may therefore include:

  • how participants will organise and administer substance-group activity;
  • how costs associated with shared work or information will be allocated;
  • how confidentiality and commercially sensitive information will be managed in practice;
  • how differences in classification and labelling will be addressed; and
  • how efficiently groups will be able to respond where HSE requests further information.

The draft already provides mechanisms allowing certain information to be submitted separately in specified circumstances, including disproportionate cost, commercially sensitive information likely to cause substantial commercial detriment, and disagreement over the information selected for joint submission.

The consultation nevertheless provides an opportunity to consider whether the wider framework gives registrants sufficient clarity to make substance groups workable in practice.

 

Classification and EU REACH alignment deserve careful review

Another area that warrants close attention is the relationship between UK REACH submissions and classification information generated under EU legislation.

Under the proposed arrangements, registrants would in certain circumstances need to confirm consistency with an applicable harmonised classification under EU CLP or, where there is no such classification, a classification submitted by the EU REACH lead registrant and published by ECHA.

Where the registrant’s classification differs, reasons would need to be provided. Where classification is not possible, that would also need to be explained.

This does not mean that EU classifications are simply imported into UK REACH. However, it does make the relationship between a registrant’s position and relevant EU classification information operationally important.

Businesses may therefore want to review whether their existing classifications align with the relevant information identified in the proposed legislation and whether they could clearly explain any differences.

For some registrants, this may require additional work during preparation of their ATRm submission or subsequently if the classification position is examined by HSE or discussed within a substance group.

 

Reduced data requirements do not necessarily remove data-access challenges

One of the policy objectives behind ATRm is to reduce the burden associated with reproducing EU REACH registration datasets within the UK system. The proposed legislation seeks to achieve this in part by reducing the information that certain transitional registrants would need to submit routinely, while retaining mechanisms for information sharing and cost sharing between registrants.

However, reduced submission requirements do not necessarily mean that access to underlying information will cease to matter.

The draft provisions envisage circumstances in which registrants may need to exchange information within substance groups, explain classification differences or provide further information following a transitional evaluation decision. In some cases, the relevant information may already exist within EU REACH registrations or may be held by other registrants or third parties.

The proposed legislation contains data-sharing and cost-sharing mechanisms, but an important practical question is how effectively those arrangements will operate where access to relevant information depends on existing commercial agreements, data ownership or cooperation between different parties.

This may be relatively straightforward for some businesses. Existing consortium arrangements, data-sharing agreements, Letters of Access or other contractual rights may already provide access to relevant information.

For others, the position may be less clear.

Registrants may therefore want to assess:

  • what information they already have rights to access and use, rather than simply what information exists;
  • whether existing contractual or data-sharing arrangements extend to the uses contemplated under ATRm;
  • whether additional access rights, permissions or commercial agreements could be required if HSE requests information that is not currently held by the registrant;
  • how responsibilities would operate where relevant information is controlled by other registrants or third parties; and
  • whether any uncertainty around access could create costs, delays or practical difficulties that should be raised through the consultation.

More broadly, stakeholders may wish to consider whether the proposed framework could create situations in which registrants need information they do not directly control. Where compliance depends on information held by third parties, the practical operation of the regime may be influenced as much by commercial access arrangements as by the legal requirements themselves.

This distinction is important when assessing the overall burden of ATRm. The benefits of reduced upfront submission requirements will depend partly on whether businesses can obtain and use the information they still need without creating disproportionate administrative or commercial costs.

 

The consultation provides an opportunity to test the legislation against real registrations

Defra is seeking feedback on the draft legal provisions before the legislation is finalised, including potential drafting issues, ambiguities, omissions, procedural gaps and unintended consequences.

This makes the current consultation particularly relevant for businesses able to test the proposed provisions against real registration circumstances.

Rather than revisiting the general merits of ATRm, registrants can examine whether the proposed legislation produces practical difficulties when applied to their substances, supply chains and existing data arrangements.

Questions worth considering include:

  • Which of our transitional registrations would be subject to the alternative information requirements?
  • Are there circumstances in which the eligibility conditions produce unclear or unintended outcomes?
  • How would substance-group participation work for the substances we manufacture or import?
  • Are our classifications consistent with the information referenced by the proposed legislation, and could any differences be explained?
  • What information could HSE request through transitional evaluation?
  • Do we have the necessary rights to access and use that information if it is held elsewhere?
  • Could joint submission, data sharing or substance-group participation create additional costs or administrative requirements?
  • Are there provisions whose practical effect is unclear when applied to an actual registration?

These questions can help distinguish a general response to the policy from an evidence-based response to the proposed legislation.

 

Potential themes for consultation responses

Each organisation’s circumstances will differ, but our initial review suggests stakeholders may wish to consider whether the proposals provide sufficient clarity regarding:

  • the operation and governance of substance groups;
  • allocation of costs associated with shared activities and information;
  • access to information required to meet ATRm obligations;
  • circumstances in which HSE may exercise transitional evaluation powers;
  • timelines associated with requests for further information;
  • practical implementation of classification alignment requirements; and
  • unintended consequences arising from the interaction between UK REACH and EU REACH arrangements.

These are the types of implementation issues that may benefit from stakeholder evidence before the legislation is finalised.

 

What should businesses do now?

The consultation closes on 10 November 2026, leaving a relatively short period for affected organisations to assess the proposals.

Rather than viewing ATRm purely as a reduction in registration requirements, businesses should consider how the proposed framework would operate across their UK REACH portfolios.

A useful review could include testing:

  • whether relevant registrations meet the conditions for the alternative information requirements;
  • what information would still need to be submitted or retained;
  • the practical implications of participating in substance groups;
  • whether existing classification positions could require further explanation;
  • whether current data-access rights are sufficient for potential future requirements;
  • how the organisation would respond to a transitional evaluation request; and
  • whether any aspect of the proposed drafting could create unintended administrative, commercial or compliance consequences.

The Government has already set out its ATRm policy conclusions. The current consultation therefore provides an important opportunity for industry to influence how those conclusions are translated into practical legal obligations.

For businesses with UK REACH registrations, the most valuable exercise may not be estimating the reduction in upfront information requirements, but identifying where the proposed framework could create uncertainty, additional costs or implementation challenges once it is in operation.

 

How RPA can help

RPA can support organisations in reviewing the ATRm proposals against their UK REACH portfolios and developing evidence-based consultation responses ahead of the consultation deadline.

This can include:

  • identifying which registrations may qualify for the alternative information requirements;
  • reviewing substance-group implications;
  • assessing classification and data-access challenges;
  • considering potential exposure to transitional evaluation requests;
  • identifying ambiguities or unintended consequences in the draft provisions; and
  • preparing consultation submissions supported by practical evidence.

With the consultation closing on 10 November 2026, organisations have a relatively short window to assess the proposals and raise relevant implementation issues before the legislation is finalised.