ESOS Phase 4 · Part 6A
ESOS action plans and progress updates: Phase 4 to 2031
Notifying compliance in December 2027 is the middle of ESOS Phase 4, not the end.
Part 6A of the Regulations adds an action plan and, since SI 2026/701, three annual progress updates that run to the end of 2031.
The dates
Four filings after the deadline
The action plan covers the next compliance period, 6 December 2027 to 5 December 2031, so it overlaps Phase 5.
Each progress update reports what has been implemented and the savings achieved against the plan.
The third update, due 5 December 2031, was added by SI 2026/701 for compliance periods ending on or after 5 December 2027.
Each filing is confirmed by the responsible officer and submitted through MESOS.
- 5 Dec 2027Notification of complianceIncluding savings achieved and the review of the Phase 3 plan.Regs 27D, 27E, 29
- 5 Dec 2028Action planMeasures to implement by 5 December 2031, with dates and kWh savings.Reg 34A
- 5 Dec 2029Initial progress updateReg 34B(1)(a)
- 5 Dec 2030Further progress updateReg 34B(1)(b)
- 5 Dec 2031Final progress updateNew in Phase 4.Reg 34B(1)(c)
New in Phase 4
The Phase 3 plan comes back for review
A Phase 4 ESOS report must now look backwards as well as forwards.
It states the energy savings achieved during the compliance period, measure by measure, in kWh.
And it identifies Phase 3 action plan measures that were not implemented, and are not expected to be, with the reasons.
Only the combined savings figure is published; per-measure savings and the reasons for unimplemented measures go to the scheme administrator alone.
A participant with zero energy consumption owes no action plan and no updates at all.
Enforcement
A published duty with no penalty
Regulations 34A and 34B are named nowhere in Part 8, so no civil penalty attaches to them.
That is a gap in the Regulations, and a stronger point than the regulator’s statement that it will not enforce.
The pressure is publicity: plans, updates and failures to submit are published, and Phase 3 plans already appear in the open data.
An enforcement notice requiring a plan would itself be enforceable under regulation 46.
The penalties page covers the offences that do exist, and the family’s ESOS Phase 4 compliance guide on uksrs.org.uk sets the plan in the full timeline.
| Filing | Penalty in Part 8? | Published? |
|---|---|---|
| Notification of compliance | Yes — reg 43 | Yes |
| Action plan | No | Yes, and failure published |
| Progress updates | No | Yes, and failure published |
In figures
The tail of Phase 4 in numbers
Frequently asked
Questions people ask
When is the ESOS Phase 4 action plan due?
By 5 December 2028, within the first year of the following compliance period, under regulation 34A.
It sets out the energy efficiency measures the organisation proposes to implement by 5 December 2031, with dates and estimated savings in kWh.
How many ESOS progress updates are there in Phase 4?
Three, due by 5 December 2029, 5 December 2030 and 5 December 2031.
SI 2026/701 added the third.
The Environment Agency’s guidance says two in some places and three in others; the Regulations require three.
What is the ESOS action plan review?
New in Phase 4: the ESOS report and notification must identify measures in the previous action plan that have not been and are not expected to be implemented, and explain why. That review is notified to the scheme administrator but not published.
Is there a penalty for not submitting an ESOS action plan?
No. None of the five civil penalties in Part 8 attaches to regulations 34A or 34B.
The failure is published by the scheme administrator, and if a regulator served an enforcement notice requiring a plan, failing to comply with that notice would be penalisable.
Are ESOS action plans published?
Yes.
Regulation 10 requires the scheme administrator to publish each action plan and each progress update.
Phase 3 action plans and first progress updates were released as open data in June 2026.
Sources
Primary sources
Every figure, date and status on this page traces to the instrument’s owner.
Secondary commentary is never the source for a number.
- legislation.gov.ukSI 2014/1643 Part 6A — action plans and progress updates
Regulations 34A and 34B.
- legislation.gov.ukSI 2014/1643 regulation 34B — progress updates
Three progress updates for periods ending on or after 5 December 2027.
- legislation.gov.ukThe Energy Savings Opportunity Scheme (Amendment) Regulations 2026 (SI 2026/701), in force 22 July 2026
Every Phase 4 change: routes, savings reporting, the action plan review, the third progress update.
- legislation.gov.ukSI 2026/701 — Explanatory Note
The government’s own summary of what the 2026 amendments do.
- legislation.gov.ukThe Energy Savings Opportunity Scheme Regulations 2014 (SI 2014/1643)
The scheme itself. The consolidated text does not yet show the 2026 amendments.
- legislation.gov.ukSI 2014/1643 regulation 4 — compliance periods, qualification and compliance dates
Generates 6 Dec 2023 – 5 Dec 2027, 31 Dec 2026 and 5 Dec 2027.
- legislation.gov.ukSI 2014/1643 Part 8 — civil penalties (regulations 39–47)
Five offences; none attaches to action plans or progress updates.
- Environment AgencyHow to comply with the Energy Savings Opportunity Scheme (ESOS) phase 4 (30 July 2026)
The regulator’s guidance; a restatement of the Regulations, never the master.
- Environment Agency / GOV.UKEnergy savings opportunity scheme (ESOS): find out if you qualify and how to comply (updated 2 September 2026)
The GOV.UK hub, now a Phase 4 page, and the approved lead assessor register list.
- data.gov.ukEnergy Savings Opportunity Scheme — published notifications and action plans
What the scheme administrator publishes.
- legislation.gov.ukSI 2014/1643 regulation 33A — zero energy consumption
Inserted by SI 2026/701: deemed compliance, but a notification is still made.