Check if ESOS 4 applies to your business

Energy Savings Opportunities Scheme
The UK Government's mandatory energy assessment

As of 2025, the Environment Agency has issued over 83 civil penalties amounting to over £1.2 million for ESOS non-compliance.

Takes around 60 seconds
Clear guidance on the next steps
START THE QUIZ below
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Step 1 of 6

Where is your organisation registered?

UK
Non-UK
Not sure

How many employees does your organisation have?

Fewer than 250
250 to 500
500 to 2,000
More than 2,000
Not sure

Approximate annual turnover last financial year?

Under £44m
£44m to £100m
Over £100m
Not sure

Does your organisation operate from one or more UK sites with significant energy use?

Yes, multiple sites
Yes, single site
No
Not sure

Do you currently have an internal energy specialist?

Yes — dedicated role
Yes — part of another role
No
Not sure

When was your last ESOS assessment?

ESOS Phase 1
ESOS Phase 2
ESOS Phase 3
Never completed

Almost there — enter your details to see if ESOS applies to your business.

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ESOS 4 applies to your business

Compliance deadline: 5 December 2027

Based on your answers, ESOS 4 applies to your business. Preparation typically starts well in advance — an egg energy expert will contact you to discuss the next steps.

You may not be eligible

Based on your answers, ESOS 4 may not apply to your business. Thank you for your interest — if you have questions about energy management, we're still here to help.

Questions about energy? Let's chat

What is ESOS?

The UK's mandatory energy assessment scheme

ESOS (Energy Savings Opportunities Scheme) is a mandatory energy assessment scheme for large UK organisations. It requires them to carry out energy audits every four years to identify ways to reduce energy consumption.

Organisations with 250+ employees must comply
Or those with an annual turnover exceeding £44m
Regulated by the Environment Agency
Non-compliance results in significant civil penalties
egg's team of experts can guide you through the full process

Enforcement to date

83+
Civil penalties issued by the Environment Agency
£1.2m
Total penalties issued for non-compliance

ESOS 4 Timeline

Now – 2025
Qualification period begins
Assess whether your organisation qualifies for ESOS 4.
2025 – 2026
Audit preparation
Gather energy data and appoint a Lead Energy Auditor.
2026 – 2027
Energy audits conducted
Site visits and energy opportunity assessments completed.
5 Dec 2027
ESOS 4 compliance deadline
All eligible organisations must notify the Environment Agency.
Post-2027
Implementation phase
Act on identified energy-saving opportunities.

Common questions

ESOS 4 FAQs

Everything you need to know about the Energy Savings Opportunities Scheme Phase 4.

ESOS Phase 4 is the fourth cycle of the UK's mandatory Energy Savings Opportunities Scheme, requiring large organisations to conduct energy audits and identify savings opportunities by 5 December 2027.
UK organisations that employ 250 or more people, or have an annual turnover exceeding £44 million and an annual balance sheet total exceeding £38 million, are required to comply.
The Environment Agency can issue civil penalties of up to £50,000 for failure to comply, plus daily penalties of up to £500 until compliance is achieved. To date, over £1.2 million in penalties have been issued.
egg's energy experts can manage the entire ESOS process for your organisation — from initial qualification checks to conducting audits, identifying savings opportunities, and submitting your compliance notification to the Environment Agency.
With the deadline of 5 December 2027, preparation should ideally start in 2025–2026 to allow sufficient time for data gathering, site audits, and reporting. Starting early also means you can implement savings sooner.