ECO guidance and associated documents

Here you can access guidance and publications on the ECO scheme.

What our guidance does

It outlines:

  • how we determine which suppliers are obligated
  • how obligated suppliers can meet their obligations
  • when and what suppliers need to report on, and
  • information on ECO measures.

The ECO3 scheme commenced on 3 December 2018 and runs until 31 March 2022. The documents below apply to all measures installed on or after 1 October.

You can find guidance on delivering ECO measures amidst COVID-19 here.

What it doesn’t do

It’s not intended as a definitive guide to the ECO3 Order.

Previous ECO schemes

Any measures installed between 1 April 2017 and 30 September 2018, should comply with our ECO2t guidance and associated documents.

Any measures installed between 1 April 2015 and 31 March 2017, should comply with our ECO2 guidance and associated documents.

If you’re unable to find the document you are looking for, contact the ECO team who will be happy to help.

ECO3 Key Scheme Resources (From 1 October 2018)


Date Published

Energy Company Obligation 2018-22 (ECO3) Guidance: Supplier Administration

31 October 2018

Energy Company Obligation 2018-22 (ECO3) Guidance: Delivery

15 November 2018

Energy Company Obligation (ECO3) Guidance: Innovation 5 February 2019



Date Published

ECO3 Pre-existing Loft Insulation Declaration

27 September 2018

ECO3 Social housing E, F and G declaration & landlord permission

28 September 2018

ECO3 Private housing FTCH declaration & private rented sector landlord permission

28 September 2018

ECO3 Boiler Assessment Checklist

02 October 2018

ECO3 Electric Storage Heater Checklist

02 October 2018

ECO3 Privacy policy

10 October 2018

ECO3 Child Benefit self-declaration

16 October 2018

ECO3 Data Dictionary

19 October 2018

ECO3 Appropriate Guarantees

14 November 2018

ECO3 Measures Table

15 November 2018

ECO3 Deemed Scores Matrix

30 November 2018

ECO3 Notification Template

3 December 2018

ECO3 Templates to evidence private domestic premises

3 December 2018

ECO3 Monitoring

25 January 2019

ECO3 Notice of receipt of an application for extension

31 January 2019

ECO3 Address formatting guidance note

31 January 2019

ECO3 Notifying a supplier of a decision to refuse or revoke approval of a measure

31 January 2019

ECO3 Alternative methodologies

31 January 2019

ECO3 District Heating Pre-Conditions (Insulation): Technical Report Template

28 March 2019

ECO3 District heating systems (DHS) factsheet and summary of proposal (SoP)

29 March 2019

ECO3 Toolkit

15 May 2019

ECO3 First Time Central Heating Pre-Conditions (Insulation): Technical Report Template

20 January 2020

Publications and updates

  • Published: 2nd Feb 2017
  • Guidance
  • 1 Associated documents
Notification template for ECO2t.

  • Published: 2nd Feb 2017
  • Guidance
  • 1 Associated documents
Data Dictionary for ECO2t.

  • Published: 6th Oct 2016
  • Decisions
  • 4 Associated documents
We have now published the response to our ECO deemed scores consultation

  • Published: 3rd Oct 2016
  • Guidance
  • 1 Associated documents
Our ECO2 cavity wall U-value checklist must be completed for all CWI measures with overwritten U-values

  • Published: 1st Sep 2016
  • Guidance
  • 2 Associated documents
Information on room in roof insulation (RIRI) measures under ECO.

  • Published: 24th Aug 2016
  • Factsheets
  • 1 Associated documents
This note describes the ECO2 de-duplication process.

  • Published: 17th Aug 2016
  • Open letters and correspondence
  • 1 Associated documents
Our response outlines our understanding of the proposed changes and where possible, details how we expect to administer the changes if the proposals become law.

  • Published: 27th Jul 2016
  • Guidance
  • 1 Associated documents
An ECO2 guidance note on determining whether premises are domestic premises.

  • Published: 6th Jul 2016
  • Guidance
  • 3 Associated documents
This document lists the guarantees that Ofgem has reviewed and consider to meet the criteria for an appropriate guarantee under the Energy Company Obligation (ECO).

  • Published: 24th Jun 2016
  • Guidance
  • 1 Associated documents
Notice on the ECO2 retrospective U-value audit.