ESOS Phase 4 Amendments: What has changed, and what you need to do?

Last week, the Environment Agency circulated its latest ESOS newsletter, announcing the ESOS Phase 4 changes that came into force on the 22^nd of July resulting from the amendment passed by the UK Government.

Compliance Routes

Green Deal Assessments (GDAs) & Display Energy Certificates (DECs) have both been removed as routes to compliance. From ESOS Phase 4, only energy audits, ISO 50001 certification or a combination of the two will be accepted.

In addition, further amendments were made specifically to compliance via ISO 50001. Previously companies were exempt from appointing a lead assessor for sign off only if 100% of their total energy was covered by ISO 50001. This exemption has been extended to cases where the significant energy consumption, excluding up to 5% de minimis, is certified. Companies where this applies will be exempt from producing a report and will not need their notification of compliance to be signed off.

This is a positive change from the last cycle, where many businesses had reporting obligations just to audit a negligible portion of their energy consumption. For example, a manufacturing business whose industrial processes are ISO certified but their small office building was not would’ve been required to complete an energy audit and report with lead assessor sign off.

Action Plan Requirements

The action plan and two related progress updates in subsequent years after the energy audits and notification of compliance were a new addition during the last cycle. Following this, the Phase 4 ESOS assessment will now be required include a review of progress against the action plan. Where commitments haven’t been met, participants must explain why.

Another related change will see operators be required to submit a third progress update as part of their Phase 4 obligations.

Phase 3 Progress Report

The second progress report on the Phase 3 action plan must be submitted through the MESOS system by the 5^th of December 2026. This is an ongoing obligation from the last phase so will only apply to those who qualified previously and were required to submit a Phase 3 notification of compliance.

For operators who did not qualify last time but may do so for Phase 4 should be aware of the upcoming qualification date on the 31^st of December 2026. Any undertaking who meets the inclusion criteria on their most recent accounts at that date, must comply with all Phase 4 deadlines.

The full ESOS Phase 4 guidance was published by the Environment Agency on the 30^th of July 2026 after the amendment to the regulations – Comply with the Energy Savings Opportunity Scheme (ESOS) phase 4

If you’d like to discuss ESOS inclusion criteria or compliance further, please contact the Swan Energy team.