KJ Tait

Heat networks 2026: HNTAS and Ofgem

Ogem Heat Networks 2026

From 27 January 2026 Ofgem begins regulating heat networks across Great Britain

What has changed for 2026

From 27 January 2026 Ofgem begins regulating heat networks across Great Britain, with registration, data reporting and consumer‑protection duties phasing in during 2026 and fuller enforcement by 2027.  Treat 2026 as the compliance start line.

The Government has also published the Heat Network Technical Assurance Scheme (HNTAS).  HNTAS turns best practice into mandatory, auditable technical requirements for new and existing communal and district systems, drawing on CIBSE CP1 and phasing in to keep the burden proportionate.

Finally, notifications and compliance data will be moved to Ofgem’s digital service in spring 2026, replacing the old OPSS notification route under the Heat Network Metering & Billing Regulations.  Meter installation and accuracy duties continue in the interim.

What HNTAS means for commercial buildings

HNTAS will require evidence that your network is engineered and operated to a clear baseline. Focus on four essentials.

  • Temperatures and hydraulics Lower primary flow temperatures, stable ΔT, balanced circuits and responsive substation controls to cut losses and improve comfort.
  • Insulation and distribution Verified insulation standards on mains, risers and laterals to reduce distribution losses and avoid unintended internal heat gains.
  • Metering and billing integrity Calibrated meters, robust data paths and billing that stands up to scrutiny, including where non‑domestic and microbusiness customers are supplied.
  • Commissioning and monitoring Evidence‑based commissioning with measurable acceptance tests, then routine monitoring and corrective actions supported by assurance routes.

Ofgem authorisation — the essentials for 2026

Ofgem is introducing authorisation conditions for all GB heat networks. Late‑2025 consultations covered registration, nominated operator accountability, regular data reporting, fair‑pricing and consumer standards, and enforcement. Final guidance now moves into implementation in 2026, with the majority of conditions enforced by 2027. Mixed‑use and multi‑occupancy sites will feel this most, because pricing transparency and service standards apply across customer groups.

Your 90‑day action plan

  1. Create a network register and gap assessment List every communal or district system, operator details, customer classes, temperature regimes, distribution losses, metering architecture and known defects. Map gaps against Ofgem’s registration and data requirements and HNTAS technical themes.
  2. Stand up the data pipeline Prepare to submit outages, complaint metrics, meter reliability, consumption and billing integrity through Ofgem’s digital service as it launches in spring. Retain current HNMBR metering duties until HNTAS supersedes technical elements.
  3. Deliver quick technical wins Lower flow temperatures where feasible, retune substation controls and upgrade insulation on risers and laterals. These reduce losses immediately and improve tenant experience.
  4. Refresh tariffs and communications Put in place a tariff review process, document cost allocation and indexation, and publish plain‑English explanations to reduce disputes as fair‑pricing guidance lands.
  5. Update contracts and SLAs Add obligations for data provision, outage response, meter accuracy, performance testing and audit rights so you can evidence compliance to Ofgem and occupiers.

Scotland — what to watch

The Scottish Government has published a draft Buildings (Heating and Energy Performance) and Heat Networks (Scotland) Bill and signalled an early 2026 consultation on installation and maintenance licences for heat networks, with legislation to follow after the May 2026 election. Engage through LHEES and prepare for licensing conditions and potential zonal connection duties.

What Has Changed for Heat Networks?

Heat networks are now regulated by Ofgem across Great Britain. The new regulatory framework introduces consumer protection requirements, registration obligations and ongoing regulatory oversight for heat network operators and suppliers.

For most organisations, the immediate priority is understanding whether registration applies to their heat network and preparing the information required by Ofgem. Existing heat network operators and suppliers must register by 26 January 2027.

Alongside the new regulatory framework, government is developing the Heat Network Technical Assurance Scheme, known as HNTAS. HNTAS is planned to launch in 2027 and will introduce technical standards, performance monitoring and assurance requirements for heat networks.

What Should Building Owners and Operators Do Now?

The first step is identifying every communal and district heat network within your portfolio and understanding who carries the regulated responsibilities for operating and supplying each network.

You should then review the information available for each network, including ownership arrangements, customer information, metering arrangements, billing processes and technical documentation required to support registration.

Organisations should also begin reviewing the quality of their metering and operational data. Reliable data will support registration, future HNTAS readiness and long-term operational performance.

What Is HNTAS?

The Heat Network Technical Assurance Scheme is being developed by government to help heat network operators demonstrate compliance with future technical standards and performance requirements.

Government guidance indicates that HNTAS will apply to both new and existing heat networks and will be introduced in phases. The scheme is intended to improve heat network performance, reliability, efficiency and consumer outcomes.

While the final scheme continues to develop, published draft documents indicate increasing emphasis on metering, monitoring, technical documentation, operational records and performance reporting.

How KJ Tait Can Help

KJ Tait supports building owners, heat network operators, suppliers and managing agents with heat network registration, HNTAS readiness reviews, metering assessments and data validation.

Our building services engineering, energy metering and operational performance expertise helps clients understand current regulatory requirements while preparing for future technical assurance obligations.

Frequently Asked Questions

When did Ofgem begin regulating heat networks?

Ofgem began regulating heat networks across Great Britain on 27 January 2026.

When is the heat network registration deadline?

Relevant existing heat network operators and suppliers must register with Ofgem by 26 January 2027.

What is heat network registration?

Heat network registration requires relevant operators and suppliers to provide Ofgem with information about their organisation, ownership, heat networks, financial resilience and consumer protection arrangements.

Is an existing heat network notification enough?

No. A notification made under the previous heat network metering and billing regime does not replace the new Ofgem registration requirement.

What is HNTAS?

HNTAS is the Heat Network Technical Assurance Scheme. It is being developed to help heat network operators demonstrate compliance with future technical standards and performance requirements.

When will HNTAS launch?

Current government guidance indicates that HNTAS is planned to launch in 2027 and will be phased in over time.

Will HNTAS apply to existing heat networks?

Yes. Government guidance indicates that the technical standards will apply to both new and existing heat networks. Existing networks are expected to receive transition periods as the requirements are phased in.

Do commercial buildings need to comply?

Potentially. The answer depends on whether the system meets the definition of a relevant heat network, which regulated activities are being carried out and which organisations act as the operator and supplier. Commercial and mixed-use developments should assess their position rather than assume they sit outside the framework.

What information is required for heat network registration?

Registration information may include organisational details, ownership arrangements, financial resilience information, heat network details and consumer protection arrangements.

What should heat network operators do now?

The immediate priorities are identifying every heat network within the portfolio, establishing operator and supplier responsibilities, preparing information for registration and reviewing the quality of available metering and operational data.