Energy Company Obligation (ECO)

Energy suppliers

This page contains information for energy suppliers on the Energy Company Obligation (ECO) scheme. All the scheme guidance documents can be found on the contacts, guidance and resources section of our website.

When do energy suppliers become obligated to take part in ECO?

Large and medium sized energy suppliers have legal obligations under the Energy Company Obligation (ECO) scheme if they meet the obligation threshold. This is determined by customer numbers and supply volumes which we will request from suppliers at specific times.

We offer advice and assistance to all newly obligated suppliers to make sure they’re prepared to take part in the scheme.

What are energy suppliers’ responsibilities?

Energy suppliers are responsible for meeting their obligations and ensuring that they, and any members of the supply chain acting on their behalf, comply with scheme requirements.

How are energy suppliers’ targets worked out?

As scheme administrator, we’re responsible for setting energy suppliers’ obligations. We do this using a calculation based on their share of the gas and electricity supply market. This is determined by the ECO4 legislation.

Trading obligations

Obligated energy suppliers have the option to trade their obligations with other obligated energy suppliers. The guidance includes information on how energy suppliers should go about trading their obligations.

ECO4 innovation

ECO4 includes incentives designed to support the delivery of innovative measures that can provide further energy efficiency improvements, or that offer additional benefits, via the new measures and products (NMAP) routes


The ECO register

Obligated energy suppliers notify us of the measures they’ve delivered by uploading them to the ECO register. For support on updating the register the ECO4 Supplier data dictionary document can help. Contact us on if you experience any problems or require access.  

How we engage with stakeholders

We believe that engaging with stakeholders when designing and delivering schemes brings real benefits and do this via forums and working groups which gather contributions from a range of stakeholders on the main operational and delivery issues in ECO.

To find out more see the section dedicated to stakeholder engagement.