WebinarClimatise Phase 4 for ESOS Providers: The Workflow That Replaces the Spreadsheet RegisterClimatise ESOS Phase 4: Replace the Spreadsheet RegisterRegister
Latest: UK SRS S1 and S2 published 25 February 2026
UK SRS Overview
UK SRS Org Logo
UK SRSSustainability Reporting Standards
ESOS · Part 6A · Action plan obligations

ESOS Action Planrequirements, deadlines, what to include

Introduced in Phase 3 via the ESOS (Amendment) Regulations 2023. Forward-looking documents covering identified energy saving measures, expected savings and implementation timelines — with two annual progress updates and board-level director sign-off.

Phase 3 action plan
5 Dec 2024 (passed)
Late window closed 5 Mar 2025
Submitted
Annual updates
5 Dec 2025 & 5 Dec 2026
Two board-signed progress updates required
Annual
Phase 4 integration
5 Dec 2027
Phase 4 submission must report action plan progress
01Overview

What an ESOS action plan is

Forward-looking documents under Part 6A — energy saving measures, expected savings, implementation timelines and board accountability.

02Content requirements

Six action plan elements

Forward-looking documents focused on measures and expected savings, not general energy management policy. Each element broken down by organisational purpose.

Energy saving measuresElement 1
Detailed description of specific energy saving opportunities identified during ESOS assessment, including technical specifications and implementation approaches.
Expected energy & cost savingsElement 2
Quantified estimates of energy consumption reduction (kWh/year) and associated cost savings (£/year) for each identified measure.
Implementation timelineElement 3
Realistic timescales for delivery of energy saving measures broken down by organisational purpose and operational requirements.
Investment requirementsElement 4
Capital expenditure estimates, payback periods, and financing arrangements for energy efficiency measures across organisational activities.
Organisational purpose breakdownElement 5
Allocation of measures across different organisational purposes — demonstrating systematic approach to energy efficiency improvement.
Monitoring & verification planElement 6
Framework for tracking implementation progress and measuring actual energy savings achieved against projected targets.
03Deadlines & timeline

Action plan timeline through Phase 4

One primary deadline, one late window, two annual progress updates, then Phase 4 progress reporting.

  1. 5 DEC 2024Phase 3 action plan deadline
  2. 5 MAR 2025Late submission window closed
  3. 5 DEC 2027Phase 4 compliance + progress reporting
2

Annual progress updates required

Two board-signed updates due 5 December 2025 and 5 December 2026.

Each reports implementation progress against action plan commitments and is subject to public disclosure.

SI 2023/1182
04Annual progress updates

What progress updates must cover

Board-signed and publicly disclosed. Five content categories from implementation status through additional measures beyond the original plan.

Implementation statusRequired content
Per-measure implementation status against the original action plan commitments. Track each measure individually.
Actual savings achievedRequired content
Energy savings (kWh) and cost savings (£) realised, not just projected. Compare against the action plan estimates.
Variance explanationsRequired content
Where targets not met, narrative explanation. Acceptable reasons include site closure, business change, or technical infeasibility discovered during implementation.
Revised timelinesRequired content
Updated implementation timelines for delayed measures, with rationale for the revision.
Additional measuresRequired content
Energy efficiency measures implemented beyond the original plan. Demonstrates continuous improvement beyond the minimum action plan scope.
05Public disclosure

Public register & disclosure obligations

Action plans and progress updates are publicly disclosed. The Environment Agency maintains a participant register with compliance status and high-level savings opportunities.

06Phase 4 integration

Phase 3 commitments → Phase 4 reporting

Phase 4 ESOS assessments must include reporting on action plan progress. Where commitments weren't met, organisations must explain — alternative measures, revised plans, lessons learned.

07Enforcement

Current enforcement position

No specific penalties currently defined for action plan submission failure — but non-compliance is identified through public disclosure, creating reputational accountability.

08ESOS action plan deadline

ESOS action plan deadline — Phase 3 submission

The Phase 3 ESOS action plan deadline was 5 December 2024 with a late window to 5 March 2025; annual progress updates follow on 5 December 2025 and 5 December 2026.

ESOS action plan deadline: the headline submission date under Part 6A was 5 December 2024 for the Phase 3 cycle, with late submissions accepted without remedial action up to 5 March 2025. Two board-signed annual progress updates then fall due on 5 December 2025 and 5 December 2026 before Phase 4 progress reporting at the next ESOS Phase 4 deadline on 5 December 2027.

Submissions go through the Environment Agency’s MESOS system as part of the wider ESOS compliance regime. Action plans and progress updates are published on the public participant register, so plan content should be appropriate for disclosure while maintaining commercial sensitivity around specific operational details.

ESOS action plan deadline — 5 December 2024 Phase 3 submission and 5 December 2026 annual progress update timeline
09ESOS action plan guidance

ESOS action plan guidance, submission and support

Official guidance, submission mechanics and support routes for organisations preparing or revising their ESOS action plan.

For organisations preparing Part 6A documents, ESOS action plan guidance is published by the Department for Energy Security & Net Zero (DESNZ) and the Environment Agency. Read it alongside the 10ESOS (Amendment) Regulations 2023, which set out the six required elements: measures, expected savings, timelines, investment requirements, organisational-purpose breakdown and monitoring & verification.

ESOS action plan guidanceAuthority source
Official guidance is published on GOV.UK under the ESOS scheme overview. Read it together with the 2023 Amendment Regulations (SI 2023/1182) and the Environment Agency MESOS submission notes.
ESOS action plan submissionProcess
ESOS action plan submission is via the MESOS notification system operated by the Environment Agency. Board-level director sign-off is mandatory before submission, and the action plan is then published on the public participant register.
ESOS action plan supportPractical routes
Organisations seeking ESOS action plan support typically engage a lead assessor from an approved register or use internal energy managers with appropriate certification. Trade bodies (e.g. ESTA) and DESNZ webinars provide free reference material.
ESOS action plan content checklistPre-submission review
Quick checklist: (1) six required elements present, (2) figures broken down by organisational purpose, (3) implementation timelines realistic, (4) board director identified for sign-off, (5) content suitable for public disclosure.
10FAQ

ESOS action plan — frequently asked questions

Direct answers covering introduction date, Phase 3 deadline, progress update obligations, Phase 4 integration and current enforcement position.

What is an ESOS action plan and when was it introduced?

ESOS action plans were introduced in Phase 3 through the 2023 Amendment Regulations.

They are forward-looking documents detailing energy saving measures identified during ESOS assessment, expected savings, and implementation timelines broken down by organizational purpose.

When is the ESOS Phase 3 action plan deadline?

The Phase 3 action plan deadline was 5 December 2024.

Late submissions are accepted without remedial action up to 5 March 2025, though organizations should submit as soon as possible to demonstrate regulatory compliance.

What are ESOS progress updates and when are they due?

Organizations must submit annual progress updates on 5 December 2025 and 5 December 2026 reporting implementation progress against action plan commitments.

Updates require board-level sign-off and are subject to public disclosure.

How do action plans connect to Phase 4 requirements?

Phase 4 ESOS assessments must include reporting on action plan progress.

Where action plan commitments have not been met, organizations must provide explanation in their Phase 4 compliance submission.

Are there penalties for not submitting an action plan?

Currently there are no specific penalties for action plan or progress update submission failure, but non-compliance is identified through public disclosure.

Organizations should submit to demonstrate regulatory compliance and energy management commitment.

Continue reading

Related guides & references

Authority Sources

  1. ESOS (Amendment) Regulations 2023 (SI 2023/1182, UK Parliament)
  2. Energy Savings Opportunity Scheme (ESOS) — Overview (gov.uk, updated 16 Feb 2026)
  3. ESOS Dataset (data.gov.uk, ongoing)
  4. ESOS Post-Implementation Review 2025 (DESNZ, 2025)