Registering a heat network with Ofgem: who must do it, by when, and what if you don't

Most of this site is about heat network zoning, which isn't law yet. This guide is about a duty that already exists and has a fixed date. If you run a heat network, or you're a landlord whose building has communal heating, you almost certainly need to register it with Ofgem. Here is who that applies to, the deadline, how to do it and what happens if you don't.

The deadline

That date isn't arbitrary. Ofgem became the regulator for heat networks on 27 January 2026[source], and the regulations give existing networks until the end of the first year to register. You may see 27 January quoted in Ofgem's original guidance document, but the regulations and Ofgem's own registration pages both say 26 January, so plan for that. Don't plan for the last week either. Large landlords may have dozens or hundreds of networks to register, and the information takes time to pull together.

There's a second date to know about if you're building something new.

So a scheme that starts supplying heat on 27 January 2027 or later can't rely on the automatic authorisation that existing networks have. If you're a developer with a scheme due to complete around then, talk to Ofgem early.

Who must register

The duty is based on what you do, not what kind of organisation you are. Registration applies to the operator and the supplier of each heat network, which can be the same organisation[source]. Ofgem explains the two roles like this: the operator controls and is responsible for the network, even if a contractor does the day-to-day work. The supplier handles the customer side, such as setting charges, issuing bills and handling complaints.

The networks in scope are district heat networks serving 2 or more buildings, and communal heat networks serving one building divided into separate premises[source]. That second category is the one that catches people out. A block of flats with a single plant room feeding every flat is a heat network in Ofgem's eyes. So is an office building with a central system supplying separately let units.

Some small set-ups are outside the rules altogether: a single house in multiple occupation, or a single converted building with one heat source of no more than 45 kWth[source]. Read Ofgem's who should register page carefully before relying on one of these exclusions, because the wording matters. For example, a building of self-contained flats that counts as a house in multiple occupation under a different part of the housing law isn't covered by the exclusion.

Landlords, freeholders and managing agents

If you own or manage residential blocks, the key question is who the operator is. Ofgem's guidance says that in a leasehold block the operator is typically the freeholder, though it may be a Right to Manage or residents' management company[source].

That has some practical consequences.

• Managing agents often run the heating day to day, but that alone doesn't usually make them the operator. Ofgem looks at who has control and responsibility, so check your management agreement.
• Billing agents may send the bills, but the supplier is the party responsible for the customer relationship. If you use a metering and billing company, it can help you gather information, but the registration duty is still yours.
• Housing associations and councils with communal heating are treated in the same way as any other operator or supplier. Rules on how charges are recovered can differ where heat is paid through rent or service charges, which our guide for landlords and leaseholders covers.
• Right to Manage and residents' management companies may take on the operator role, depending on the arrangements.

Common situations

A few examples show how the role-based test tends to play out. Treat them as starting points for your own check against Ofgem's guidance, not as rulings.

A university with halls of residence on a campus network. One energy centre serving several buildings is a district network. If students or other occupiers are charged for heat, directly or as part of their rent, the university is likely to be both operator and supplier.

An office building with tenants on a central system. If the building is divided into separately let units and the landlord recovers heating costs from tenants, it is likely to be a communal network, even though nobody lives there.

A block where an ESCO supplies residents. The ESCO may be the supplier while the freeholder remains the operator, or the ESCO may hold both roles. Your contract with the ESCO should make this clear. If it doesn't, ask.

A care home with shared heating. Ofgem lists single buildings with shared facilities that aren't divided into separate premises as outside scope, and gives care homes as an example.

Where it's genuinely unclear who the operator or supplier is, sort that out before you register, and take legal advice if leases or contracts are involved. The person who registers takes on the obligations that come with it.

How to register

In practice the process runs in stages. Your organisation's regulatory contact requests access to the service. Ofgem says it aims to confirm access within 10 working days, so don't leave that step until January. You then add your organisation's details, complete fit and proper declarations for the people with significant influence over the business, and add colleagues. After that you register each network.

For each network, expect to provide information on where it is and how it's configured, the energy centre and heat source, the number and type of customers, how heat is metered, how customers are billed, and the consumer protections you have in place. Suppliers create their own account but can only add their supply role once the operator invites them.

Ofgem says registration isn't an approval process. Once you submit it, the network is registered and gets a reference number. That doesn't mean the information doesn't matter. Ofgem will use it to plan its oversight, and it is an offence under the regulations to give information you know to be false or misleading.

Two other conditions fall due on the same date and are worth doing alongside registration: a register of material assets and a continuity plan must be in place by the end of 26 January 2027[source].

What happens if you don't register

The answer has two parts, and it's worth being precise.

First, existing networks are already authorised: anyone operating or supplying a heat network before the end of 26 January 2027 is treated as authorised[source]. So missing the deadline doesn't make your network illegal overnight. It does mean you're breaching one of the conditions attached to that authorisation.

Second, breaching a condition gives Ofgem enforcement options. It can make an order requiring you to comply, and it can impose a penalty.

That is the ceiling, not the starting point. Ofgem has said how it intends to start: its priority in the first year is to understand the sector, with more serious action where firms don't engage, customers are harmed or it needs to deter others[source]. That's reassuring for an organisation that is trying and running late, but it's no reason to sit tight. Ignoring registration is the clearest example of not engaging.

There is a harder line for new schemes. Operating or supplying without authorisation is a criminal offence, punishable in England and Wales by a fine with no upper limit[source]. That's the position for someone who starts operating or supplying without authorisation once automatic authorisation has ended, not for an existing network that is late to register.

Your customers' rights in the meantime

Registration sits alongside consumer protections that already apply. The consumer advocate is Citizens Advice, for heat network consumers in England and Wales[source], and the Energy Ombudsman accepts heat network disputes, usually after 8 weeks with the supplier[source]. If your role includes supply, Ofgem says you must also register with the Energy Ombudsman's heat network supplier scheme. Make sure your complaints process and bills tell residents and tenants where they can go next.

Where to get help

Start with Ofgem. Its help and support page explains how to contact the heat networks team before and after you register, and its guidance index links to the registration, consumer protection, pricing and enforcement guidance. The how to prepare for registration page lists what each stage asks for.

If you have many networks, unclear records or questions about who the operator is, outside help can save time. Our directory lists firms offering Ofgem authorisation and regulation support, and metering and billing specialists can help with customer and billing information. If you'd rather not choose yourself, get matched and we'll pass your enquiry to up to three listed firms. For the bigger picture, including the technical standards that come next, read our guide to Ofgem regulation and HNTAS, and see the timeline for every date in one place.