ECO3 Notice of receipt of an application for extension


Publication date

Industry sector

Supply and Retail Market

Scheme name


This update explains how we let energy suppliers know that we have received an application to extend the notification deadline for a completed measure under the Energy Company Obligation (ECO). It also explains what happens once we have assessed the application.

Where a supplier notifies measures after the notification deadline, these can be dealt with in two ways: 

  1. The notification deadline is automatically extended for up to three months for a maximum of 5% of measures, or 
  2. A supplier can apply for an extension to the notification deadline. 

Where a supplier applies for an extension to the notification deadline for a measure we expect the application to be made promptly by the supplier when it first becomes aware that it has, or will, fail to notify a measure by the notification deadline. 

The application must be made in writing and must include a reason explaining why an extension is being requested. We will then assess the application. The supplier must satisfy us that it has a reasonable excuse for failing to notify by the notification deadline which must be supported by evidence. For further information on applications for extensions please see our guidance for suppliers

We will provide suppliers with a notice of receipt of an extension application once a supplier has submitted an application to us. Our notice of receipt will include the following: 

  • extension reference number
  • supplier license code
  • measure reference number
  • measure type
  • date of installation

Please see an example of the notice, below.

Once we have assessed the application we decide whether to grant the extension to the notification deadline. We then issue a letter to the supplier notifying them of our decision. This letter details the extension reference number assigned to the extension application. If we approve the request, the letter will also state the date by which the measure(s) should be notified.