ESOS Assessments
ESOS Assessments
Lead assessor-led ESOS compliance for large organisations — energy audits, reporting, and full sign-off to meet your legal obligations.
What is ESOS?
The Energy Savings Opportunity Scheme (ESOS) is a mandatory energy assessment scheme for large UK organisations. Qualifying organisations must carry out ESOS assessments every four years, covering their buildings, industrial processes, and transport energy use.
ESOS assessments must be led and signed off by a Lead Assessor — a qualified professional registered with a recognised professional body. WM Sustainability provides the full ESOS service, from initial qualification checks through to Environment Agency notification.
Do you qualify?
Your organisation qualifies for ESOS if it employs 250 or more people, or has an annual turnover exceeding €50 million and a balance sheet exceeding €43 million. Subsidiary companies may also qualify through their parent organisation.
ESOS Phases
Current compliance phase
ESOS Phase 3 compliance notifications were due by 5 June 2024. If your organisation has not yet complied, you should act promptly to avoid enforcement action. We can assist with late compliance and advise on your obligations for ESOS Phase 4.
Phase 1
December 2015
Closed
Phase 2
December 2019
Closed
Phase 3
June 2024
Closed — late compliance available
Phase 4
TBC 2027
Preparation advised
Our Process
How we work
Qualification Check
We confirm whether your organisation qualifies for ESOS and identify all qualifying group undertakings that must be included in the assessment.
Energy Data Collection
We gather 12 months of energy consumption data across all qualifying assets — buildings, transport, and industrial processes.
Energy Audits
Our Lead Assessor conducts energy audits across your significant energy consumption areas, identifying opportunities for savings.
Report & Notification
We produce the ESOS assessment report, obtain Lead Assessor sign-off, and submit your notification to the Environment Agency before the compliance deadline.
Ensure your ESOS compliance
Talk to our Lead Assessor about your organisation's obligations and how we can manage the full process for you.