UK ETS: Guidance for ultra small emitters
Source: gov.uk (2025-10-15)

Relevant information for ultra small emitters (USEs) on eligibility and compliance.

You don’t need to participate in the UK Emissions Trading Scheme if your installation emits less than 2,500 tonnes of carbon dioxide equivalent (CO2eq) in the relevant period.

You can instead register your installation as an ‘ultra-small emitter’ (USE) under the Ultra-small Emitter scheme. You must continue to monitor your emissions and notify the regulator if your emissions exceed the agreed threshold.

This guidance tells you:
- which installations are eligible to join the USE list
- how to monitor your emissions as a USE
- what to do if your installation no longer qualifies as a USE
Aircraft operators cannot apply to register as ultra-small emitters. Read separate guidance for aircraft operators with low emissions (https://www.gov.uk/guidance/complying-with-the-uk-ets-as-an-aircraft-operator).

Eligibility

Eligibility for the 2021 to 2025 allocation period

Your installation is classed as a USE if it is included in the ultra-small emitter list for the 2021 to 2025 allocation period.
- List of ultra-small emitters for the 2021 to 2025 allocation period (https://assets.publishing.service.gov.uk/media/611285738fa8f506cd8008c6/uk-article-27-27a-installation-list.ods) (ODS, 26.8 KB)
There will be no new USEs during this allocation period.

Installations on the ultra-small emitters list for 2021 to 2025 had their greenhouse gas emissions permit or excluded installation emissions permit revoked in December 2020, as a permit is no longer required.

Eligibility for the 2026 to 2030 allocation period

Your installation will be considered a USE in the 2026 to 2030 period if it is included in the ultra-small emitter list for 2026 to 2030.
- List of ultra-small emitters for the 2026 to 2030 allocation period (https://assets.publishing.service.gov.uk/media/68ef4c208427701993d5e09f/use-list-2026-2030.ods) (ODS, 15 KB)
Eligible installations must have met one of the following conditions:
- if you were carrying out a regulated activity at your installation on or before 1 January 2021, your installation’s reportable emissions were 2,499 tonnes of CO2eq or below in scheme years 2021, 2022 and 2023
- if you commenced a regulated activity at your installation between 2 January 2021 and 1 January 2022, your installation’s reportable emissions were 2,499 tonnes of CO2eq or below in scheme years 2022, 2023 and 2024
- if you commenced a regulated activity at your installation between 2 January 2022 and 1 January 2023, your installation’s reportable emissions were 2,499 tonnes of CO2eq or below in scheme years 2023 and 2024
- if you commenced a regulated activity at your installation between 2 January 2023 and 1 January 2024, your installation’s reportable emissions were 2,499 tonnes of CO2eq or below in scheme year 2024
How to apply for USE status for the 2026 to 2030 allocation period

The window to apply to join the Ultra Small Emitter list for 2026-2030 has now closed.

Regulator contact details

If you have any queries, please contact your regulator using the following contact details:
- for sites in England - the Environment Agency (EA) at xxx@xxx.xx (mailto:xxx@xxx.xx)
- for sites in Scotland - the Scottish Environment Protection Agency (SEPA) at xxx@xxx.xx (mailto:xxx@xxx.xx)
- for sites in Wales - Natural Resources Wales (NRW) at xxx@xxx.xx (mailto:xxx@xxx.xx)
- for sites in Northern Ireland - the Northern Ireland Environment Agency (NIEA) at xxx@xxx.xx (mailto:xxx@xxx.xx)
After you have submitted your application

The regulator will revoke any existing greenhouse gas emissions permit or hospital or small emitter permit.

You do not need any type of UK ETS permit during the period in which your installation is a USE.

How to monitor your emissions

You must monitor your emissions and notify your regulator if you emit more than 2,500 tonnes of CO2eq in any scheme year.

To monitor your emissions, you must follow the methodology set out in your monitoring plan. Your plan must be kept up to date in line with the provisions in the UK ETS Order and must ensure this remains fit for purpose.

If your installation no longer qualifies as an ultra-small emitter

Your installation cannot voluntarily cease to be a USE during the allocation periods.

Your installation will no longer be a USE if its reportable emissions exceed 2,500t CO2eq in either:
- any of the 2021 to 2023 scheme years in relation to the 2021 to 2025 allocation period
- any of the 2026 to 2028 scheme years in relation to the 2026 to 2030 allocation period
If your installation ceases to be a USE, you must notify your regulator by 31 March of that scheme year. If you do not, you will be liable to a civil penalty.

Your regulator will then send you a notice requiring you to either:
- join the UK ETS main scheme (https://www.gov.uk/government/publications/participating-in-the-uk-ets)
- join the Hospital and Small Emitter scheme (https://www.gov.uk/guidance/opt-out-of-the-uk-ets-if-your-installation-is-a-hospital-or-small-emitter) (if you meet the eligibility criteria)
You must then apply for either a greenhouse gas emissions permit or a hospital or small emitter permit.

You will remain liable for any unpaid penalties and any further sanctions applied for non-payment of those penalties arising from your time as a USE.