You report ESOS compliance by submitting a notification of compliance through the government’s Manage your Energy Savings Opportunity Scheme service, known as MESOS. For Phase 4, the notification must be submitted by 5 December 2027.
The notification includes information about the organisation and its corporate group, the compliance routes used, total or significant energy consumption, energy intensity ratios and the ESOS Lead Assessor where one is required. It also includes information about the energy-saving opportunities identified, energy savings achieved since the previous compliance period and, where applicable, a review of the previous ESOS Action Plan.
Before the notification is submitted, the ESOS assessment must receive the required director-level sign-off. Where a Lead Assessor is required, the notification must also confirm whether they consider the assessment to comply with the ESOS requirements.
The organisation must keep supporting information in an evidence pack, including its calculations, energy audits, records of the compliance routes used and director approvals. Regulators can request this evidence if the organisation is selected for a compliance check.
ESOS reporting continues after the main compliance notification. Organisations must submit an Action Plan through MESOS, followed by annual Progress Updates reporting the measures implemented and the energy savings achieved.
The Environment Agency publishes most of the information submitted in the notification of compliance, although personal and commercially sensitive information is excluded.
