ESOS Newsletter August 2026 Issue 44

Publication of Phase 3 Progress Update 1 Data

The Phase 3 Progress Update 1 dataset contains data from initial progress updates submitted by participants by 5 June 2026 following the submission of their Phase 3 notifications of compliance (NOCs) and Action Plans.

The data includes:

• the name of the organisation

• updates on the measures that ESOS participants propose to implement by 5 December 2027 (the end of the Phase 4 compliance period)

• the total energy savings estimated to be achieved from implementing each measure

• whether the reason for implementing the measure relates to another scheme or requirement

• whether the measure has now been implemented

• if so, whether it was implemented by the date proposed in the action plan

• whether there has been a reduction in energy consumption for the period between 6 December 2024 and 5 December 2025 and / or 6 December 2023 and 5 December 2024

• estimation methods used to calculate energy savings

• any context to proposed measures (where provided).

Updated Publication of Phase 3 Notification of Compliance (NOC) and Action Plan Data datasets

Direct links to the latest Phase 3 Notification of Compliance and Phase 3 Action Plan datasets were shared in Issue 42 of the March 2026 newsletter.

Both datasets have now been updated. The Phase 3 Notification of Compliance Data Publication now includes all Notification of Compliance (NOC) data submitted up to 5 June 2026. The Phase 3 Action Plan Data Publication has also been updated and now includes all Action Plan data submitted up to 5 June 2026.

Notification of Compliance and Action Plan data Q&A

What are the compliance rates for NOCs, action plans and initial progress updates?

Over 86% of ESOS participants are now compliant with these requirements, with more organisations currently being brought into compliance.

What is happening to organisations that have not submitted a NOC, action plan or initial progress update?

The legislation requires all organisations that qualify for ESOS to submit a NOC, action plan and initial progress update, including where no measures are proposed to be implemented in the action plan. Organisations that have not addressed these requirements are being investigated by the compliance bodies (the Environment Agency in England and other regulators for the devolved regions and offshore waters) and enforcement action may be taken against them.

If I have not submitted a NOC, action plan or initial progress update can I still do so?

Those organisations that have not addressed these requirements may be at risk of enforcement action and should contact the Environment Agency immediately for advice on what to do next.

MESOS User Management

Organisations should regularly review and maintain their contacts within the MESOS reporting system to ensure information remains accurate and up to date. Removing outdated contacts, such as individuals who have changed roles or left the organisation, helps protect sensitive information, prevents missed communications, and reduces the risk of unauthorised access.

Adding new users to the organisation account

1. Select ‘Users and Accounts’.

2. Select from the ‘add a new user’ dropdown box the user type you are wishing to add. The options are ‘Advanced User’ or ‘Restricted User’ with guidance on these different user types being given on the link below the drop-down box. Press continue.

3. Add the first name, last name and email address of the individual you are adding as a user.

4. An email will be sent to that new user to confirm their identity and create their login credentials.

5. Once this has been actioned you will need to change the users status from ‘Accepted’ to ‘Active’ which will then allow the user to sign in to the organisation account.

Disabling or removing a user from your account

1. Select ‘Users and Accounts’.

2. In order to disable the user from your account on the user line change their account status to ‘Disabled’.

3. In order to remove the user from your account completely on the user line select ‘Remove’.

GOV.​UK One Login rollout to MESOS

As detailed in our recent newsletters we have introduced a new way to sign in to the Manage your Energy Savings Opportunity Scheme Reporting system (MESOS), using GOV.​UK One Login. This is the new secure way to access government services and will be rolled out across more services in the future.

Upon signing into MESOS, users can now connect their MESOS accounts to One Login – please go to the MESOS sign in page and refer to the steps at Annex A – One Login Guidance below.

Annex A – One Login Guidance

Connecting GOV.​UK One Login to your MESOS account

1. Select ‘Start now’. You’ll be taken to GOV.​UK One Login, where you can create a GOV.​UK One Login if you do not already have one.

2. GOV.​UK One Login will return you to the MESOS service.

3. Choose to connect your existing MESOS account to your GOV.​UK One Login.

4. Confirm your identity using your MESOS sign in details.

Once connected, you’ll use GOV.​UK One Login to access your MESOS account from then on.

If you have forgotten your MESOS sign in details

Resetting either a password or a two-factor authenticator app (2FA) for your MESOS account

1. During the process of connecting GOV.​UK One Login to your MESOS account, you will be asked to enter your email address and confirm your identity using your existing MESOS password and 2FA.

2. If you need to reset your password, use the ‘I have forgotten or want to change my password’ link.

3. If you need to reset your authenticator app, use the ‘I have lost access to my authenticator app’ link.

4. You will receive an email which will allow you to reset either your password or your 2FA app. Please ensure that Junk/Spam folders are also checked for these emails.

5. If you still cannot sign in after following these steps, contact the ESOS IT helpdesk.

Resetting both the password and two-factor authenticator app (2FA) for your MESOS account

1. You must first reset one of the details, either your password or the 2FA app.

2. When you are asked for the other detail, select ‘I have forgotten my password and lost access to my authenticator app’.

3. You will be taken to the ‘Reset MESOS account password and authenticator app’ form.

4. Enter your name and the email address you use to sign in to MESOS.

5. Submit the form. You’ll get an email confirming that your request has been received. Once your request has been processed, you’ll get another email with a link and instructions on how to reset your MESOS sign in details. Please ensure that Junk/Spam folders are also checked for these emails.

END OF NEWSLETTER