ESOS Phase 4

Do we need ESOS?

A short guide for hospitality operators, plus a simple checker. This is not legal advice. Always confirm against the latest GOV.UK guidance.

Guided scope check: £19 one-off. If you are likely in scope, you get 20% off your first 3 months of Essential or Premium with code HES20 at checkout.

What is ESOS?

The Energy Savings Opportunity Scheme is a UK mandatory energy assessment for large undertakings and their corporate groups.

Qualification date

31 December 2026: whether you qualify is judged on this date (Phase 4).

Compliance notification

Notify by 5 December 2027 if you qualify for Phase 4.

Large undertaking

250+ people employed, or turnover over £44m and balance sheet over £38m.

Groups

If any UK group member is large, the whole UK group generally participates.

Worth knowing

A few points from the GOV.UK guidance that are easy to miss. ESOS assessments run every 4 years, so it is worth keeping an eye on this even if you are out of scope today.

  • Overseas companies: if your business is a UK branch or registered establishment of an overseas company, it must take part whatever its own size, as long as the group’s UK activities meet the large undertaking tests.
  • In before, out now: if you qualified in an earlier phase, or the regulator has been in touch, but you don’t qualify for Phase 4, you still need to tell your regulator that you don’t qualify.
  • Phase 3 progress update: if you qualified in Phase 3, your annual action plan progress update is due by 5 December 2026. It must be signed off by a board-level director and submitted through MESOS, the online ESOS reporting system.

Source: GOV.UK: Energy Savings Opportunity Scheme (updated 2 September 2026).

Simple checker

Answer a few questions about your organisation on the Phase 4 qualification date (31 December 2026). Indicative only. Edge cases (recent growth/shrink, overseas structures) need the full GOV.UK guidance.

1. On 31 Dec 2026, will you employ 250 or more people?

Include employees, owner-managers and partners. Part-time and full-time count the same.

2. Is annual turnover over £44 million and balance sheet total over £38 million?

Both financial tests must be met together. Use the accounts year ending on or in the 12 months before 31 Dec 2026.

3. Are you part of a UK corporate group where any UK member is a large undertaking?

If any UK group company meets the large tests, the UK group generally takes part.

4. Are you a public body?

Public sector organisations are generally excluded from ESOS.

If you may need ESOS

  1. Book the £19 guided scope check.
  2. If you are likely in scope, use code HES20 when you subscribe to Essential or Premium for 20% off your first 3 months.
  3. Read the official guidance on GOV.UK: Energy Savings Opportunity Scheme.
  4. Ask us for an introduction to a qualified ESOS partner. We do not carry out the assessment ourselves.