Everything you need to know about UK REACH: obligations, DUIN, registration and grandfathering

18/7/2025

Context: What is UK REACH?

Since January 2021, UK REACH is the regulation in force in Great Britain for the registration, evaluation, and authorisation of chemical substances. It was implemented after the UK left the European Union (EU), replacing the EU REACH regulation, which no longer applies in Great Britain.

UK REACH applies to all companies operating in Great Britain and introduces new regulatory obligations, particularly for businesses that previously relied on registrations made under EU REACH.

Which companies are affected by UK REACH?

Companies based in Great Britain that were previously considered downstream users of substances registered under EU REACH are now regarded as importers of chemical substances under UK REACH. They must therefore register these substances with the relevant UK authority: the Health and Safety Executive (HSE).

Submitting a Downstream User Import Notification (DUIN)

To reduce the administrative burden, the UK introduced a simplified procedure: the DUIN (Downstream User Import Notification). This notification allows UK-based companies to inform the HSE that they import chemical substances from:

  • The European Union
  • A third country via an Only Representative (OR) based in the EU

đź’ˇ This notification provides a deferral period of 1, 3, or 5 years before a full registration under UK REACH is required.

Eligibility requirements for a DUIN

To be eligible to submit a DUIN, the following conditions must be met:

  • The substance must have been registered under EU REACH before 31 December 2020
  • The substance must have been imported into the UK between 1 January 2019 and 31 December 2020

If these conditions are not met, a full registration under UK REACH will be required immediately.

Deadlines after submitting a DUIN

Once a DUIN has been submitted, full registration must be completed based on the tonnage and properties of the substance:

đź“… 27 October 2026 (previously 2 years from 28 October 2021)

  • Substances: ≥ 1000 tonnes/year
  • CMR substances (carcinogenic, mutagenic, toxic to reproduction): ≥ 1 tonne/year
  • Substances very toxic to aquatic life: ≥ 100 tonnes/year
  • Substances on the candidate list as of 31 December 2023

đź“… 27 October 2028 (previously 4 years from 28 October 2021)

  • Substances: ≥ 100 tonnes/year
  • Substances on the candidate list as of 27 October 2026

đź“… 27 October 2030 (previously 6 years from 28 October 2021)

  • Substances: ≥ 1 tonne/year

Steps to submit a DUIN

The DUIN notification must be submitted via the official “Comply with UK REACH” portal. The required information varies depending on the volume imported:

For imports of 1–10 tonnes/year:

  • Identity of the manufacturer/importer
  • Substance identity
  • Classification and labelling
  • Existing restrictions and authorisations
  • ECHA registration number (if available)
  • Any other relevant information for risk management

For imports >10 tonnes/year, also include:

  • Chemical safety report and risk management measures
  • Safety Data Sheets (SDS)

Grandfathering: Recognition of an EU REACH Registration

What is Grandfathering?

Grandfathering applies to UK-based companies that held an EU REACH registration between 29 March 2017 and 31 December 2020.

This provision allows the transfer of an existing EU REACH registration to UK REACH without having to restart the process from scratch.

Grandfathering steps

  • Create an account on the “Comply with UK REACH” portal
  • Submit initial information (proof of EU REACH registration, substance identity, uses, etc.)
  • Obtain a UK REACH registration number
  • Negotiate data sharing with other registrants
  • Finalise the full registration within the applicable deadline, based on tonnage

Registration under UK REACH

Who needs to register?

Any company that manufactures or imports a substance in quantities over 1 tonne per year in Great Britain must complete a registration.

Steps for registration under UK REACH

  • Start with an inquiry (Article 26) to check if a registration already exists
  • Join or create a joint registration (following the “one substance, one registration” principle)
  • Appoint a Lead Registrant for data sharing
  • Submit the registration dossier via the “Comply with UK REACH” portal

đź’ˇ UK REACH is based on the same principles as its European counterpart:

  • “No data, no market”
  • Data sharing
  • Reduction of animal testing
  • Precautionary risk management

To learn more about REACH authorisation in the UK, see our article: “UK REACH and Authorisations: How to Stay Compliant in the UK.”

Appointing an Only Representative (OR) in the UK

Companies not established in the UK can appoint a local Only Representative (OR) to handle their UK REACH obligations, including DUIN submissions and full registrations.

For more information, check out our article: “UK REACH: Do I Need to Appoint an Only Representative (OR)?”

Need help achieving compliance?

As a specialist in REACH and REACH-like regulations, EcoMundo can support you at every stage:

  • DUIN submissions
  • Grandfathering
  • Full registration
  • Tailored regulatory support

Feel free to contact us!

Context: What is UK REACH?

Since January 2021, UK REACH is the regulation in force in Great Britain for the registration, evaluation, and authorisation of chemical substances. It was implemented after the UK left the European Union (EU), replacing the EU REACH regulation, which no longer applies in Great Britain.

UK REACH applies to all companies operating in Great Britain and introduces new regulatory obligations, particularly for businesses that previously relied on registrations made under EU REACH.

Which companies are affected by UK REACH?

Companies based in Great Britain that were previously considered downstream users of substances registered under EU REACH are now regarded as importers of chemical substances under UK REACH. They must therefore register these substances with the relevant UK authority: the Health and Safety Executive (HSE).

Submitting a Downstream User Import Notification (DUIN)

To reduce the administrative burden, the UK introduced a simplified procedure: the DUIN (Downstream User Import Notification). This notification allows UK-based companies to inform the HSE that they import chemical substances from:

  • The European Union
  • A third country via an Only Representative (OR) based in the EU

đź’ˇ This notification provides a deferral period of 1, 3, or 5 years before a full registration under UK REACH is required.

Eligibility requirements for a DUIN

To be eligible to submit a DUIN, the following conditions must be met:

  • The substance must have been registered under EU REACH before 31 December 2020
  • The substance must have been imported into the UK between 1 January 2019 and 31 December 2020

If these conditions are not met, a full registration under UK REACH will be required immediately.

Deadlines after submitting a DUIN

Once a DUIN has been submitted, full registration must be completed based on the tonnage and properties of the substance:

đź“… 27 October 2026 (previously 2 years from 28 October 2021)

  • Substances: ≥ 1000 tonnes/year
  • CMR substances (carcinogenic, mutagenic, toxic to reproduction): ≥ 1 tonne/year
  • Substances very toxic to aquatic life: ≥ 100 tonnes/year
  • Substances on the candidate list as of 31 December 2023

đź“… 27 October 2028 (previously 4 years from 28 October 2021)

  • Substances: ≥ 100 tonnes/year
  • Substances on the candidate list as of 27 October 2026

đź“… 27 October 2030 (previously 6 years from 28 October 2021)

  • Substances: ≥ 1 tonne/year

Steps to submit a DUIN

The DUIN notification must be submitted via the official “Comply with UK REACH” portal. The required information varies depending on the volume imported:

For imports of 1–10 tonnes/year:

  • Identity of the manufacturer/importer
  • Substance identity
  • Classification and labelling
  • Existing restrictions and authorisations
  • ECHA registration number (if available)
  • Any other relevant information for risk management

For imports >10 tonnes/year, also include:

  • Chemical safety report and risk management measures
  • Safety Data Sheets (SDS)

Grandfathering: Recognition of an EU REACH Registration

What is Grandfathering?

Grandfathering applies to UK-based companies that held an EU REACH registration between 29 March 2017 and 31 December 2020.

This provision allows the transfer of an existing EU REACH registration to UK REACH without having to restart the process from scratch.

Grandfathering steps

  • Create an account on the “Comply with UK REACH” portal
  • Submit initial information (proof of EU REACH registration, substance identity, uses, etc.)
  • Obtain a UK REACH registration number
  • Negotiate data sharing with other registrants
  • Finalise the full registration within the applicable deadline, based on tonnage

Registration under UK REACH

Who needs to register?

Any company that manufactures or imports a substance in quantities over 1 tonne per year in Great Britain must complete a registration.

Steps for registration under UK REACH

  • Start with an inquiry (Article 26) to check if a registration already exists
  • Join or create a joint registration (following the “one substance, one registration” principle)
  • Appoint a Lead Registrant for data sharing
  • Submit the registration dossier via the “Comply with UK REACH” portal

đź’ˇ UK REACH is based on the same principles as its European counterpart:

  • “No data, no market”
  • Data sharing
  • Reduction of animal testing
  • Precautionary risk management

To learn more about REACH authorisation in the UK, see our article: “UK REACH and Authorisations: How to Stay Compliant in the UK.”

Appointing an Only Representative (OR) in the UK

Companies not established in the UK can appoint a local Only Representative (OR) to handle their UK REACH obligations, including DUIN submissions and full registrations.

For more information, check out our article: “UK REACH: Do I Need to Appoint an Only Representative (OR)?”

Need help achieving compliance?

As a specialist in REACH and REACH-like regulations, EcoMundo can support you at every stage:

  • DUIN submissions
  • Grandfathering
  • Full registration
  • Tailored regulatory support

Feel free to contact us!