Inside the UK REACH ATRm 2026 and What Businesses Should Do Next

A reform years in the making, finally landing

Chemical compliance in Great Britain has been stuck in a holding pattern since Brexit. When the UK left the EU, around 20,000 substances registered under EU REACH did not transfer across to the Health and Safety Executive (HSE), meaning UK businesses faced re-registering them through a process called transitional registration.

That original model was costly. The government's own impact assessment put the total burden on UK industry at up to £2 billion by 2030, much of it driven by the need to negotiate or purchase access to hazard data packages held by EU industry consortia. Chemical sector respondents to the consultation described the situation as system paralysis, with new restrictions stalling and many businesses unable to progress registrations at all.

On 30 March 2026, the Department for Environment, Food and Rural Affairs (Defra) published the government response to its consultation on an Alternative Transitional Registration Model (ATRm). The document confirms a fundamentally lighter approach, designed to remove the upfront data wall without weakening the protections that UK REACH exists to deliver. The consultation itself ran from May to July 2024 and drew 241 responses from across the chemicals sector, NGOs, trade bodies and downstream users.

If your business manufactures, imports or uses chemicals on the GB market, this is the reform you have been waiting for. It does not let anyone off the hook, but it does change what compliance looks like in practical terms.

What the ATRm changes, and what stays exactly the same

The most significant shift is in what registrants have to submit. Under the original model, transitional registrations required full use and exposure datasets, much of which had to be purchased or licensed from EU consortia. Under the ATRm, registrants submit hazard conclusions, a summary of what is already known about a substance's hazard profile. The HSE retains the power to request fuller data on a case-by-case basis, but the default position has moved from data-heavy to risk-proportionate.

The second shift is one of regulatory alignment. The government has confirmed that UK REACH will take EU regulatory decisions as its starting point unless there are compelling reasons to diverge. For businesses that were already compliant under EU REACH before Brexit, that translates into a meaningful reduction in duplication. You should also know that the requirement to buy into EU hazard data packages is now largely off the table for transitional registrations, which removes the single biggest cost driver in the original projection.

It is worth pointing out what has not changed. The "no data, no market" principle is still the backbone of UK REACH. You cannot place a substance on the GB market without registering it. CLP classification, derived no-effect levels and PBT assessment conclusions still belong in submissions. Chemical Safety Assessments and Chemical Safety Reports are still required for substances at over 10 tonnes per annum. Safety Data Sheet requirements under CLP have not changed. COSHH duties under the Control of Substances Hazardous to Health Regulations 2002 have not changed. The reform is to the depth of information required upfront, not the obligation to register or to control.

If anything, the importance of well-maintained SDS records and COSHH assessments goes up under the ATRm, because the hazard conclusions you submit will draw directly from the same hazard information that lives in those documents. For multi-site operations or businesses with sprawling substance lists, keeping SDS records current across every location has been a quiet liability for years. The ECHA candidate list updates twice a year, classifications shift, suppliers replace formulations, and any of those movements can leave a site's records out of step with the substance actually on the shelf. A centralised, regularly updated SDS database takes that liability off the line manager's plate and turns it into something the system handles automatically. (Sevron offers this as a free search tool, no account needed.)

The new deadlines, by tonnage and hazard

The original deadlines of October 2026, 2028 and 2030 are gone. Following a separate consultation on extending submission deadlines, the government selected Option 1, which moves the first deadline back by three years and applies one-year intervals between the bands.

The new dates land as follows. 27 October 2029 applies to substances manufactured or imported at 1,000 tonnes per annum or above, to carcinogens, mutagens and reproductive toxicants (CMRs), and to Substances of Very High Concern (SVHCs) added to the candidate list before 31 December 2023. 27 October 2030 applies to substances at 100 tonnes per annum or above, and to SVHCs added to the candidate list between 1 January 2024 and 27 October 2026. 27 October 2031 applies to substances at 1 tonne per annum or above.

The dates are staggered deliberately, with the highest hazard and highest tonnage substances landing first, then mid-tier, then the long tail. Compliance check deadlines under Article 41(5) have been aligned to follow each submission deadline, so the HSE is not checking dossiers before the data has actually arrived.

The ATRm is also part of something wider. Defra has confirmed that proposals on restriction procedures, reporting processes and improvements to how the system handles new evidence will be incorporated into a broader UK REACH reform package, also expected during 2026. The first public consultation on the inclusion of 15 SVHCs already opened in March 2026, signalling that the candidate list itself is moving again after years of standstill.

What this means in practice, sector by sector

Picture the email that lands while you are already mid-meeting. A supplier flags that a substance you have been bringing in under EU REACH authorisations needs a fresh look for the GB market. A year ago, that email would have triggered a scramble through scattered folders, a worried call to a consortium, and a quiet panic about data costs. Under the ATRm, the same email triggers a calmer process. Pull the hazard conclusions you already hold, check what the HSE has signalled it will accept, and book the work into a calendar that stretches to 2029 rather than next October.

The change is real, but the change is also conditional. The full ATRm legislative framework is still being finalised, with further consultation expected through 2026 and 2027. Businesses that wait for total clarity before doing anything will arrive at 2029 underprepared. Businesses that get their substance inventory in order now will arrive ready. What that looks like depends on your sector.

Manufacturing and chemical importers

Manufacturers and importers carry the registration obligation directly. The work to do now is portfolio mapping. Which of your substances fall into the 1,000+ tonne band, which sit at 100+, which at 1+? Which are classified as CMR or sit on the SVHC candidate list, and from which date? The 2029 deadline lands first for the most hazardous and highest-volume substances, so the prioritisation cannot wait.

Manufacturing operations that hold COSHH assessments for their substances are already part-way there. The hazard data inside a well-maintained COSHH file is the same hazard data that feeds a hazard conclusions submission. The trick is making sure it stays current, which is the kind of work that our COSHH Assessment system is built to handle automatically.

Downstream users and DUIN holders

If your business has been operating under a Downstream User Import Notification (DUIN) because it relied on EU REACH authorisations held by an EU or EEA entity, the DUIN obligations remain fully in force throughout the transitional period. The deadline extensions do not change your existing notification duties. They do change when you must convert that DUIN into a full registration, which now aligns with the tonnage and hazard profile of the substance in question.

The risk for downstream users is assuming the deadline extension means a pause on everything. It does not. A DUIN that lapses, or a notification that goes stale, becomes a live compliance gap regardless of what is happening to the ATRm legislation in 2026 or 2027.

Pharmaceuticals, agriculture and SMEs

For pharmaceutical and agricultural businesses using regulated chemical inputs, the ATRm is largely good news. The reduced data burden and the alignment with EU regulatory decisions mean fewer parallel datasets to maintain. SMEs benefit disproportionately, since the £2 billion cost burden under the original model fell hardest on smaller businesses without the consortium scale to spread it.

The one watchpoint for these sectors is supplier dependency. If a critical raw material comes from a supplier that has not confirmed its GB strategy, the ATRm does not solve that for you. It just gives you more time to find out.

Reforms like the ATRm shift the burden from one type of work to another. The £2 billion data wall comes down. What replaces it is a steady demand for current, well-organised hazard information, kept in step with regulatory updates as they land. That kind of ongoing work is precisely what manual processes struggle with, and precisely what a purpose-built compliance platform makes manageable.

Safety365 pulls COSHH assessments, SDS management, Risk Assessment and incident records into one place, with SPOT AI (our homegrown AI, trained on more than twenty years of UK health and safety regulatory experience) embedded across the workflow. Our Accelerated Compliance framework runs the user through three stages: Certified through training, Competent through guided onboarding and tooling, and Compliant through automated reminders, audit trails and live SDS updates. For chemical-handling businesses preparing for the 2029 ATRm deadlines, that means the substance inventory, the hazard data, the assessments and the audit trail all live in the same system, ready to convert into a hazard conclusions submission when the time arrives.

The reform is good news. The work it implies is real. Getting your house in order now is the quiet move that pays off in 2029.

Frequently Asked Questions

Does the ATRm mean my business no longer needs to register chemicals under UK REACH?

No. Registration remains mandatory and the "no data, no market" principle is fully retained. The ATRm changes what information must be submitted at the point of registration, replacing full use and exposure datasets with hazard conclusions. The obligation to register every substance placed on the GB market is unchanged.

When does my business need to act?

That depends on the tonnage and hazard profile of your substances. The 27 October 2029 deadline applies to substances at 1,000 tonnes per annum or above, to CMRs, and to SVHCs listed before 31 December 2023. The 2030 deadline covers 100+ tonne substances and SVHCs added between 1 January 2024 and 27 October 2026. The 2031 deadline catches the 1+ tonne band. Whichever deadline applies, the work to scope your portfolio and gather hazard information should start now.

Do Safety Data Sheet duties change under the ATRm?

No. SDS requirements under CLP are unchanged and remain fully in force. The hazard information that feeds your SDS records is the same information that will feed your hazard conclusions submission, which is one reason keeping SDS records current matters more than ever.

What about COSHH assessments?

COSHH duties under the Control of Substances Hazardous to Health Regulations 2002 are unchanged. The reform is to UK REACH transitional registration, which sits upstream of COSHH. If anything, a well-maintained COSHH programme makes ATRm preparation easier, because the hazard data overlaps significantly.

Has the wider UK REACH framework been finalised?

Not yet. The ATRm policy direction is confirmed, but the full legislative framework is being finalised through 2026 and 2027. Defra has also signalled a broader UK REACH reform package covering restriction procedures and reporting, also expected in 2026. Tracking Defra and HSE publications is now part of the chemical compliance routine.

Where can I read the official government response?

The Defra government response published on 30 March 2026 is available on gov.uk. The separate consultation on deadline extensions, which confirmed the 2029, 2030 and 2031 dates, sits here.

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If your team is preparing for the 2029 deadline and wants the substance inventory, hazard data and assessments in one place, speak to us about how Safety365 fits into the work.