Connections Offer Process

This page includes information about the connections offer process. We’ve split the process into five parts, each of which contain step-by-step guidance on roles and responsibilities. There are also links to relevant resources, but if you can’t find what you’re looking for then please contact us.

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Download an interactive PDF


The five-part Connections offer process

1. Pre-application

If you’re a new customer applying for a contract with us for the first time, or an existing customer applying for a new project, you’ll need to have a pre-application conversation. Here’s how:

  1. Complete the pre-application form and send it to us

  2. We’ll organise an initial conversation

  3. Then we’ll organise the pre-application meeting

  4. The pre-application meeting will include you, us (ESO) and the TO

  5. Any follow up actions or questions will be raised and actioned

  6. Allowing you to move to the next stage if applicable

If you already have an existing contract, pre-application conversations held ahead of a Modification application, are likely to be brief and held with the ESO Contract Manager only, depending on the change to the contract.

2. Application submission

You will need to complete the application form that relates to the type of contract you’re looking for. This is what’s involved in this part of the process:

  1. Submit an application form

  2. Submit DRC data

  3. We’ll check and confirm your application

  4. Then we’ll raise your application fee invoice

  5. We’ll notify the TO of your application

  6. The TO will complete a competency review of the DRC data

  7. Pay the application fee

  8. We’ll confirm the ‘clock start’

The process is the same for new applications and modifications to existing agreements. The only difference is the application form.

3. CUSC offer period

Once your application clock has started, we have three months to issue your connection offer. This is what’s happening during that time:

  1. A kick-off meeting between us and the TO

  2. A conversation with you to address any issues or questions

  3. The TO will assess what works are needed

  4. A call between you, us and the TO to discuss connection options

  5. The TO creates a TOCO for us

  6. We review the TOCO and create an offer

  7. We all meet to discuss the offer

  8. We release the offer to you

We’ll make sure you’re kept up to speed throughout the offer period by your ESO Connections Contract Manager.

4. Offer review / signing period

Once you’ve received our contract offer, you have three months to review it and ask any questions. These are the steps in this part of the process:

  1. Review the contract offer

  2. Sign the offer and return it to us

  3. We will countersign and execute the contract

  4. We’ll provide you with a copy of the executed agreement

  5. We’ll add you to the relevant registers (e.g. TEC)

  6. You place security

This process assumes the offer is signed but there are other options available to you. You could let the offer lapse or refer it to Ofgem. In some cases, we may issue a re-offer.

5. Continuous engagement

Once you become a contracted party we’ll assign you an ESO Connections Contract Manager for the duration of your project. This includes pre-commissioning and post-commissioning. Your ESO Connections Contract Manager is your primary contact for any queries or changes you wish to make to your agreement with us. You will also have contacts within the TO who can help you with anything relating to development, construction or delivery of your project.


What to expect in your offer

Our interactive PDF will give you a good overview of what you can expect to see in your contract offer from us. It includes high level explanations of each of the offer elements as well as links to relevant resources.

Download the PDF

How to complete your application

The PDF also gives you helpful guidance on how to complete your application. If you need more help, then one of our Connection Contract Managers will be happy to talk you through the process.

Download the PDF

Connection and use of System code (CUSC) Customer Guides

Customer guides give an overview of processes or concepts within the CUSC. These guides are designed to provide detail and context to the contents of the CUSC.

Customer Security

The purpose of the guidance document is to set out the detailed process that the ESO will follow when Interactivity is been identified and notified by the Relevant Transmission Licensee that two or more offers have become interactive with each other.

The process set out in the document is consistent with the process that will be followed by the other network operators within Great Britain.


Managing your Connection journey

This high level guide covers your connection process from start to finish. From your application to changes to your contract, compliance and commissioning, and finally connection or disconnection.



Got a question? Search our bank of frequently asked questions.