Carbon emissions trading and reporting schemes

Energy Savings Opportunity Scheme (ESOS)


If you are a large business or organisation, or are part of a larger business grouping, you may have responsibilities for assessing your energy usage on a four-year cycle and find ways to become more energy efficient.

What is the Energy Savings Opportunity Scheme?

The Energy Savings Opportunity Scheme (ESOS) scheme requires large organisations in the United Kingdom to assess their energy usage and find new ways to save energy.

Large organisations include:

  • a corporate body or partnership
  • an unincorporated association carrying on a trade or business, with or without a view to profit

For the third compliance period (2019-2023) large organisations in scope are those which at 31 December 2022:

  • employ 250 or more people
  • have an annual turnover in excess of £44 million and an annual balance sheet total in excess of £38 million

How to comply with the Energy Savings Opportunity Scheme

If you qualify for ESOS and your organisation is fully covered by ISO 50001, you do not need to carry out an ESOS assessment. You just need to notify the Environment Agency that you’re compliant with ESOS.

If you qualify for ESOS, but your organisation is not fully covered by ISO 50001, you need to carry out an ESOS assessment. The assessment helps you work out what your organisation needs to do to comply with the ESOS regulations.

The assessment takes into account energy directly covered by Display Energy Certificates (DECs), Green Deal Assessments (GDAs), or ISO 50001.

For your ESOS assessment, you need to:

The Environment Agency is the UK scheme administrator, and the Northern Ireland Environment Agency (NIEA) is the regulator for organisations whose registered office is in NI – for more information on ESOS you can email

Find out more about ESOS on the GOV.UK website.