Inset companies

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Here you’ll find an overview of what an inset appointment is, how it works and who to speak to if you’d like to know more.

The inset regime

The inset regime allows a third party (an ‘inset appointee’) to become a new service provider within an existing water company’s region. Successful applicants provide water and/or sewerage services for a specific area, typically a new or large development.

There are three circumstances in which a new appointment can be granted:

  • The unserved criterion: Your site has no existing water or sewer connections. Areas such as these are known as ‘green’ sites. Locations where these connections have been destroyed or capped off are known as ‘brown’ sites.
  • The consent criterion: The existing local monopoly supplier agrees to transfer your site or premises to another company.
  • The large user criterion: Your site uses 50 million litres of water or more per year. This also applies for new appointments for sewerage services.

If you wish to make an inset application, please contact our Wholesale Market Services team for an initial discussion on 0800 009 3975. Lines are open Monday to Friday, 9am to 5pm.

Alternatively, fill out the form below and the team will contact you to take you through the process and the requirements for your development site.


Please fill out the form below, and the team will contact you to take you through the process and requirements for your development site. Alternatively, if you wish to discuss your application prior to submitting it, please contact Wholesale Market Services here.

Inset agreements

An inset appointee providing water services must have access to an adequate bulk supply. This will be via an agreed ‘point of connection’, usually at the site boundary.

Similarly, those providing wastewater services will need an agreed ‘point of discharge’ into our sewerage network.

The supply of these services is governed by legal agreements, which are negotiated between the parties.

Inset agreements are also known as ‘new appointments and variations’ by the economic regulator, Ofwat.

How to contact us

If you have any inset enquiries, please email our contracts and account management team. We’ll acknowledge receipt of your email within 24 hours.