Heat networks regulation: regular data reporting guidance

We are consulting on data reporting guidance for heat networks. This consultation follows our authorisation and regulatory oversight consultation, published on 7 November 2024. We analysed the responses to this consultation published our decision on 8 August 2025. We are now seeking views on this draft guidance to support heat network suppliers and operators to submit data to us. We will use this data to help us monitor their performance. The guidance provides: * details of the data that must be reported to Ofgem * the segments who must report data * the reporting periods and timings for submission We would like views from people with an interest in heat networks and particularly welcome responses from: * heat network operators * heat network suppliers * energy service companies * housing providers * consumer groups * asset owners * metering and billing agents * trade associations We would also welcome responses from other stakeholders and the public. ## Before you start Read the ‘Heat networks regulation: regular data reporting guidance' consultation and draft guidance document. You will find them in the ‘Related’ section on this page. Please refer to the guidance document when giving us your views. ## Why your views matter Your feedback will help us further develop our first draft of data reporting guidance that will describe the reporting obligations for heat network suppliers and operators. --- Consultation Heat networks regulation: regular data reporting guidance Publication date: Tuesday 18 November 2025 Response deadline: Monday 12 January 2026 Team: Email: Heat networks team heatnetworksregulation@ofgem.gov.uk We are consulting on our draft guidance for data reporting for heat networks. We developed this guidance using feedback from our Heat Networks regulation: Authorisation and Regulatory Oversight consultation, as well as additional stakeholder engagement. This guidance will support heat network suppliers and operators to submit data to us to help us monitor their performance. The guidance provides: • details of the data that must be reported to Ofgem • • the segments who must report data the reporting periods and timings for submission We have published the draft guidance alongside this consultation. Both this consultation and the draft guidance should be considered alongside the updated list of authorisation conditions in our Heat networks regulation: authorisation conditions published with our Heat networks regulation: authorisation conditions consultation. We would like views from people with an interest in heat networks and particularly welcome responses from: • heat network operators • heat network suppliers • energy service companies • housing providers • consumer groups • asset owners • metering and billing agents • trade associations We also welcome responses from other stakeholders with an interest in heat network regulation, and the general public. Consultation Heat networks regulation: regular data reporting guidance © Crown copyright 2025 The text of this document may be reproduced (excluding logos) under and in accordance with the terms of the Open Government Licence. Without prejudice to the generality of the terms of the Open Government Licence, the material that is reproduced must be acknowledged as Crown copyright and the document title of this document must be specified in that acknowledgement. This publication is available at www.ofgem.gov.uk. Any enquiries regarding the use and re-use of this information resource should be sent to psi@nationalarchives.gsi.gov.uk. 2 Consultation Heat networks regulation: regular data reporting guidance Contents Executive Summary............................................................................................. 4 How to respond ....................................................................................................... 5 Your response, data, and confidentiality .................................................................... 5 How to track the progress of the consultation ............................................................ 6 Send us your feedback ............................................................................................. 6 1. Guidance on regular data reporting .................................................................. 7 Context ................................................................................................................... 7 Privacy policy .............................................................................. 9 Appendix 1. Personal data .......................................................................................................... 9 Consultation Heat networks regulation: regular data reporting guidance Executive Summary Ofgem has been appointed by government as the regulator for heat networks and from 27 January 2026, a suite of consumer protection conditions will apply to heat networks. The aim of the new regulatory regime is to deliver good outcomes for heat networks customers. In particular, we want to ensure heat network customers are treated fairly, receive clear and transparent information about their heat supply, a reliable service and fair prices. In developing the detailed Authorisation Conditions underpinning these outcomes, we are introducing a framework that aims to be proportionate, cost effective and drives improvements in consumer outcomes, while delivering a stable regulatory framework which supports investment. As part of this, we are introducing a monitoring regime that will be our primary source of data on the heat network market. This consultation builds on previous publications including the Authorisation & Oversight Decision and the Fair Pricing Protections response. It is intended to provide stakeholders with further detail on the proposed data that will be reported to us. Our previous publications have helped to develop a monitoring regime and provide further understanding of the sector to inform our policy work. The monitoring regime itself will be designed to enhance our understanding of the sector as we take on our new regulatory role and assist us in shaping our approach to regulating this sector. It will also support our approach to compliance, where we will work with the sector to embed the new consumer protection requirements. A common piece of feedback from stakeholders has been to introduce guidance to support industry in meeting their requirements. We are now consulting on our first draft of guidance for heat networks, and their data obligations. The guidance will outline the monitoring framework and engagement that will be expected between authorised persons and Ofgem. It will detail: • the data points that we will require suppliers and operators to submit on an ongoing basis, either on a quarterly or annual basis • which segments of the market are not required to provide that data It is important for authorised entities to understand what their obligations are to ensure they are submitting timely and accurate information. Alongside the data reporting guidance, we will provide a data reporting walkthrough ahead of the data collection requirements starting. Whilst guidance will focus on the framework and how to meet the reporting obligations, the walkthrough will take users through how to use the digital service to provide the required information. Developing future guidance As we continue to gather data on the market through our monitoring regime and other sources of intelligence, we will continue to review both our approach to monitoring and 4 Consultation Heat networks regulation: regular data reporting guidance future iterations of data reporting guidance. As well as using our own findings we are also keen for stakeholders to provide feedback regarding what other areas future guidance could cover. Next steps This consultation closes on 12 January 2026. Feedback received will be used to finalise this first iteration of guidance on data reporting which will be published soon after regulatory commencement in January 2026. How to respond We want to hear from anyone interested in this consultation. Please send your response to the person or team named on the front page of this document. We have asked for your feedback in each of the questions throughout. Please respond to each one as fully as you can. We will publish non-confidential responses on our website. Your response, data, and confidentiality You can ask us to keep your response, or parts of your response, confidential. We will respect this, subject to obligations to disclose information. For example, under the Freedom of Information Act 2000, the Environmental Information Regulations 2004, statutory directions, court orders, government regulations, or where you give us explicit permission to disclose. If you do want us to keep your response confidential, please clearly mark this on your response and explain why. If you wish us to keep part of your response confidential, please clearly mark those parts of your response that you do wish to be kept confidential and those that you do not wish to be kept confidential. Please put the confidential material in a separate appendix to your response. If necessary, we will contact you to discuss which parts of the information in your response should be kept confidential and which can be published. We might ask for reasons why. If the information you give in your response contains personal data under the General Data Protection Regulation (Regulation (EU) 2016/679) as retained in domestic law following the United Kingdom's withdrawal from the European Union ("UK GDPR"), the Gas and Electricity Markets Authority will be the data controller for the purposes of GDPR. Ofgem uses the information in responses in performing its statutory functions and in accordance with section 105 of the Utilities Act 2000. Please refer to our Privacy Notice on consultations, see Appendix 4. If you wish to respond confidentially, we will keep your response confidential, but we will publish the number, but not the names, of confidential responses we receive. We will not link responses to respondents if we publish a summary of responses, and we 5 Consultation Heat networks regulation: regular data reporting guidance will evaluate each response on its own merits without undermining your right to confidentiality. How to track the progress of the consultation You can track the progress of a consultation from upcoming to decision status using the ‘notify me’ function on a consultation page when published on our website. Choose the notify me button and enter your email address into the pop-up window and submit. ofgem.gov.uk/consultations Once subscribed to the notifications for a particular consultation, you will receive an email to notify you when it has changed status. Our consultation stages are: Upcoming > Open > Closed (awaiting decision) > Closed (with decision) Send us your feedback We believe that consultation is at the heart of good policy development. We are keen to receive your comments about this consultation. We would also like to get your answers to these questions: · Do you have any comments about the quality of this document? · Do you have any comments about its tone and content? · Was it easy to read and understand? Or could it have been better written? · Are its conclusions balanced? · Did it make reasoned recommendations? · Do you have any further comments? Please send your feedback to stakeholders@ofgem.gov.uk. 6 Consultation Heat networks regulation: regular data reporting guidance 1. Guidance on regular data reporting Our monitoring obligations are designed to enhance our understanding of the sector as we take on our new regulatory role, and assist us in shaping our approach to regulating this sector. Our regular data monitoring guidance is spilt into two chapters. The first chapter outlines the process for providing the data to Ofgem. It also highlights the relevant legal obligations that authorised persons are required to meet regarding the provision of data. The second chapter breaks down the data we require to be submitted on an ongoing basis. This will reflect the authorisation conditions that apply to an authorised person and Ofgem’s need to protect consumers. This chapter also addresses the submission periods and the deadline for reporting the data. Questions Q1. Do you agree that the descriptions of the data points are clear? Are there any data points where we could provide a clearer description? Q2. Do you agree with the requirement to provide data back to April 2026 following registration for existing networks? If not, what would be a reasonable start date to collect data from and please state what factors would prevent your organisation from gathering and holding onto this data from April 2026? Q3. What should we consider including in a future iteration of the guidance on regular data reporting, to make it more useful? Context Data reporting will be one of the main avenues of engagement between heat networks and Ofgem. Following our authorisation and regulatory oversight decision earlier this year, our policy position resulting from our need for oversight across the market has remained the same. We want our data requests from the market to be proportionate and will only ask for data that we consider necessary, to minimise the burden placed on the sector. Within our guidance we have provided the list of data points we will require to be submitted on a regular basis. The data points we are proposing are consistent with those we have previously consulted on in the authorisation and regulatory oversight consultation and the fair pricing protections consultation. This guidance will cover how we will start data collection and the data points we expect to be submitted on a regular basis. As some authorisation conditions will not apply to all authorised persons, we will not request data if it is not needed for our regulatory oversight. We will outline whether the supplier or operator is responsible for providing the information and what segments of the industry are not required to provide each 7 Consultation Heat networks regulation: regular data reporting guidance data point. The digital service will also be designed around a heat networks requirements regarding what they do and don’t need to provide on a regular basis. A step-by-step guide on submitting the required data to the digital service will be provided separately in a monitoring assistive guide and so is not covered in this guidance. Suppliers and operators will need to start collecting regular reporting data from April 2026. The data reporting functionality that will allow users to submit the data to the digital service will be introduced later in 2026. Suppliers and operators will be able to submit the data they have held onto once both the functionality to submit to the data to the digital service is introduced and they have completed registration. This requirement to backdate data follows our authorisation and regulatory oversight decision in which we said the earliest we would backdate to would be April 2026. As our knowledge regarding the heat network market grows, we will continue to review data requirements to ensure it remains proportionate. If we make changes to data obligations, including data points to be provided or their reporting frequency, we will issue a new Request for Information and update the guidance. Changes to the ongoing requirements will include reducing the number of data points where they are no longer useful for regulatory oversight. 8 Consultation Heat networks regulation: regular data reporting guidance Appendix 1. Privacy policy Personal data The following explains your rights and gives you the information you are entitled to under the General Data Protection Regulation (GDPR). Note that this section only refers to your personal data (your name address and anything that could be used to identify you personally) not the content of your response to the consultation. 1. The identity of the controller and contact details of our Data Protection Officer The Gas and Electricity Markets Authority is the controller, (for ease of reference, “Ofgem”). The Data Protection Officer can be contacted at dpo@ofgem.gov.uk 2. Why we are collecting your personal data Your personal data is being collected as an essential part of the consultation process, so that we can contact you regarding your response and for statistical purposes. We may also use it to contact you about related matters. 3. Our legal basis for processing your personal data As a public authority, the GDPR makes provision for Ofgem to process personal data as necessary for the effective performance of a task carried out in the public interest. i.e. a consultation. 4. Your rights The data we are collecting is your personal data, and you have considerable say over what happens to it. You have the right to: • know how we use your personal data • access your personal data • have personal data corrected if it is inaccurate or incomplete • ask us to delete personal data when we no longer need it • ask us to restrict how we process your data • get your data from us and re-use it across other services • object to certain ways we use your data • be safeguarded against risks where decisions based on your data are taken • • • entirely automatically tell us if we can share your information with 3rd parties tell us your preferred frequency, content and format of our communications with you to lodge a complaint with the independent Information Commissioner (ICO) if you think we are not handling your data fairly or in accordance with the law. You can contact the ICO at https://ico.org.uk/, or telephone 0303 123 1113. 5. Your personal data will not be sent overseas 9 Consultation Heat networks regulation: regular data reporting guidance 6. Your personal data will not be used for any automated decision making. 7. Your personal data will be stored in a secure government IT system. 8. More information For more information on how Ofgem processes your data, click on the link to our “ofgem privacy promise”. 10 --- Guidance Heat networks: regular data reporting (draft) Publication date: 18 November 2025 Team: Email: Heat Networks HeatNetworksRegulation@ofgem.gov.uk This guidance is for authorised heat network suppliers and operators. It is intended to help them meet their regular data reporting requirements as outlined in the ‘Provision of information to the Authority’ authorisation condition. It describes the data that must be reported on an ongoing basis and who it is required from. It also provides further details, such as the periods that each data report should cover and the deadlines to submit the data. 1 Guidance Heat networks: regular data reporting (draft) © Crown copyright 2025 The text of this document may be reproduced (excluding logos) under and in accordance with the terms of the Open Government Licence. Without prejudice to the generality of the terms of the Open Government Licence, the material that is reproduced must be acknowledged as Crown copyright and the document title of this document must be specified in that acknowledgement. This publication is available at www.ofgem.gov.uk. Any enquiries regarding the use and re-use of this information resource should be sent to psi@nationalarchives.gsi.gov.uk. 2 Guidance Heat networks: regular data reporting (draft) Contents 1. Overview on data reporting .............................................................................. 4 Context ................................................................................................................... 4 What is data reporting .............................................................................................. 4 How will we request this data ................................................................................... 4 Authorisation Condition for requesting this data ........................................................ 5 2. Guidance on data submission .......................................................................... 6 Submission periods and deadlines ............................................................................ 6 The data we are requesting ....................................................................................... 7 Organisational level data ........................................................................................ 10 Heat network level data .......................................................................................... 13 Appendices....................................................................................................... 23 Appendix 1 – Authorisation condition – Provision of Information to the Authority . 24 Appendix 2 – Data point glossary ........................................................................ 26 3 Guidance Heat networks: regular data reporting (draft) 1. Overview on data reporting Context 1.1 This guidance is designed to help authorised heat network suppliers and operators understand their data reporting requirements. It gives general guidance on the framework, information on the quarterly and annual submission periods and describes each data point that authorised entities are required to submit. 1.2 This document should be read alongside our upcoming data reporting walkthrough which will give users step-by-step instructions on how to submit data to the digital service. What is data reporting 1.3 Data reporting forms a key part of our work to protect the interests of customers through ongoing oversight of the heat network market. Areas of particular interest include key consumer protections such as fair pricing, debt, vulnerability, and quality of service as well as the relevant financial resilience information. 1.4 Ongoing reporting from heat networks will also support our approach to compliance, where we will work with the sector to embed the new consumer protection requirements. 1.5 As well as ensuring heat network customers are protected, monitoring heat networks will improve our understanding of the market as a whole. This will help identify areas for future policy work and help inform any changes to our approach going forward. How will we request this data 1.6 Authorised persons will receive a request from Ofgem for Information which will notify them of their data reporting obligations. These requests for information will serve as our notice to authorised persons as provided for in the Heat Network Market Framework Regulations 2025. 1.7 We want our data requests from the market to be proportionate and will only ask for data that we consider necessary, in order to minimise the burden placed on the sector. Enduring information requests 1.8 To start an authorised person’s ongoing data reporting we will issue a Request for Information (RFI). This will be at a point in time after they have completed their registration or have been granted authorisation through the application process 4 Guidance Heat networks: regular data reporting (draft) and in line with the introduction of data reporting to the digital service. If we need to amend the reporting requirements laid out in guidance, for example changing the number of data points, their reporting frequency or who it is required from, we will notify authorised persons of these changes. Additional information requests 1.9 We may need additional information on top of the data that an authorised person provides through their regular data reporting obligations. In this event we will outline the data request within a separate RFI and other communications to the authorised person. Authorisation Condition for requesting this data 1.10 Under Authorisation Condition ‘Provision of Information to the Authority’, the authorised person must give necessary information to Ofgem after receiving a request from it. The ‘Provision of Information to the Authority’ condition applies to all authorised persons. An extract is in Appendix 1. 1.11 We expect information provided to us to be accurate and timely and we may take action to ensure heat networks comply with information requests. 5 Guidance Heat networks: regular data reporting (draft) 2. Guidance on data submission Submission periods and deadlines Submission periods 2.1 Suppliers and operators will be required to submit reporting data on both a quarterly and an annual basis. When an annual data submission is due, this will be done in the same reporting window as the relevant quarterly data submission. 2.2 Data should be taken as a snapshot which is the figure or value at the last calendar day of the reporting period unless specified otherwise by the data description. Deadlines 2.3 Regularly reported data may be submitted to Ofgem up to the final day of the month after the end of the quarter. Annual data submissions, with the exception of financial resilience data points, will always be required by 30 April. 2.4 Quarterly and annual submission periods and their windows are shown in tables 1 and 2 respectively as well as in figure 1. Financial data reporting 2.5 As the financial year start and end dates may vary between organisations, the point in time that financial data is prepared will also vary. To ensure that the latest data can be submitted, instead of providing financial resilience data at a fixed point in time, suppliers and operators will provide data in the next quarter following the end of their financial year. 2.6 For example, if your financial year ends between 1 January and 31 March, quarter 4, you would be required to submit financial resilience data by 31 July. Table 1: Quarterly reporting and submission windows Quarter 1 Quarter 2 Quarter 3 Quarter 4 Reporting quarter period 1 April – 30 June 1 July – 30 September 1 October – 31 December 1 January – 31 March Submission window 1 July – 31 July 1 October – 31 October 1 January – 31 January 1 April – 30 April 6 Guidance Heat networks: regular data reporting (draft) Table 2: Annual reporting period and submission window (not including financial resilience) Reporting period Annual Reporting year period 1 April (Year 1) – 31 March (Year 2) Submission window 1 April – 30 April (Year 2) Figure 1: Annual and quarterly reporting periods The data we are requesting 2.7 The below tables 3-8 outline the data we expect to be regularly reported by authorised persons. 2.8 We will not always require data to be submitted in each reporting period – for example, where we do not expect changes to the data over time. Instead, users will be required to review the data previously submitted and can confirm whether there are any changes to the currently held data or not. 2.9 Not all data points will be required from every authorised person, or both the supplier and operator in the event they are separate entities. When checking whether you need to provide the data point you should take note of the following: • whether the data point is required from the supplier or operator • • if the type of heat network is exempted and is not required to provide the data if the consumer type that the heat network exclusively supplies is exempted and is not required to provide the data • concerning organisational level data, if the authorised supplier or operator is not required to provide the data 7 Guidance Heat networks: regular data reporting (draft) 2.10 Supplier and Operators will also need to consider the level at which the data is reported, those levels being organisation and heat network. Organisation level data 2.11 Organisation level data is provided once per year by the supplier or operator. This is regardless of how many heat networks it is authorised to supply or operate . The information concerns the organisation itself that is authorised. Heat network level data 2.12 Heat network level data means the supplier or operator must provide the data point for the heat network they are supplying or operating. If it is a district heat network, data from each building or communal network on that district network should be aggregated into a single figure covering the whole district network. 2.13 For some data points such as pricing information, data may vary across parts of the heat network. In order to capture pricing differences across a heat network, users will be able to submit multiple responses to capture these differences. Backdating data 2.14 During the first part of the initial period, existing heat networks that are deemed authorised will be able to register with the digital service from April 2026 until January 2027. As data reporting will be phased in later, it will therefore be necessary for registered networks to submit information that was recorded from April 2026. Heat networks will be able to submit the data they have been collecting from April 2026, once they have completed registration and the functionality to submit data to the digital service is introduced later in 2026. Data submissions when there are no changes 2.15 We will not always require data points to be submitted each reporting period – for some data points where we do not expect change. We will instead allow for users to review their previous data submission and confirm whether there have been no changes. This will help streamline data reporting for data points less subject to change. Multiple operators and bulk supply 2.16 For heat network level data where there are multiple operators who carry out activity on a single heat network, the ‘nominated operator’ would be responsible for submitting data on behalf of the other operators on the network. We will still expect the other operators on the network to share or submit relevant reporting data that they hold but the ‘nominated operator’ will be the first point of contact. As the multiple operators are authorised entities they will still individually be required to submit their own financial reporting data. 8 Guidance Heat networks: regular data reporting (draft) 2.17 Where a supplier is supplying heating, cooling or hot water to another relevant heat network as part of a bulk supply agreement, the number of agreements should be included in the number of non-domestic customers as part of their data return. Incorrect data 2.18 In the event of incorrect data being submitted it should be rectified at the earliest opportunity with the correct information. For a step-by-step guide on amending data submissions please refer to the data reporting walkthrough. 2.19 As per regulation 62 of the Heat Network Market Framework Regulations 2025, heat networks must not provide information that the person knows to be false or misleading, or to be reckless as to whether it is. If an authorised person becomes aware that it has submitted incorrect data this should be corrected and raised to the Authority at the earliest opportunity. 9 Guidance Heat networks: regular data reporting (draft) Organisational level data The data points in table 3 are to be provided at the organisational level as described in 2.11. Reporting Interval Required by the Supplier or Operator Annual Supplier and Operator Annual Supplier and Operator Authorised entity types data is not required from Local Authorities and Registered Social Housing Providers Local Authorities and Registered Social Housing Providers Heat networks data is not required from Industrial and Self-supply Industrial and Self-supply Financial Resilience and continuity arrangements Table 3: Financial Resilience data points Data point Data point description Confirmation of a compliant Operation/Supply Continuity Plan Does the authorised entity reasonably expect to have sufficient finance and resources available to carry on its regulated heat network activity for the next 12 months? This is a yes or no response, answering whether you have an Operation/Supply Continuity Plan that is compliant with the Authorisation Condition "Continuity arrangements" and meets the requirements outlined in the relevant guidance. This is a yes or no response from the authorised entity on their financial and resource position, in order to provide an indication of the organisation's confidence in its financial health. Once the organisation has completed its financial year and has time to assure the data in its accounts or after assessing its financial position, this response should provide assurance that it expects to have sufficient resource to continue carrying out regulated activity. If an organisation does not believe they have sufficient resource to continue at any point throughout the year they should contact Ofgem in line with the ‘Availability of resource and financial responsibility principle’ authorisation condition. 10 Guidance Heat networks: regular data reporting (draft) What was the authorised entity’s net profit or loss for the previous financial year? Provided as a £ figure, this is the profit or loss after tax, with loss being provided as negative figure, for the financial year. We would expect this figure to be the same as what is submitted to other relevant regulatory bodies as part of the authorised person or entities’ accounts, not the individual heat network. Annual Supplier and Operator What was authorised entity’s total income for the previous financial year Provided as a £ figure, this is the earnings the organisation received, or receivable as reported the previous financial year. Annual Supplier and Operator What were the total running costs for the previous financial year Provided as a £ figure, this is the ongoing expenses/costs incurred by the organisation as reported from the previous financial year. Annual Supplier and Operator What is the total value of liquid assets that the authorised entity controls or has unrestricted access to Provided as a £ figure, Liquid assets are financial assets that an authorised entity has available to quickly meet its obligations. This includes cash, reserves or money received as part of a government backed loan scheme. In this instance ‘Control’ and ‘unrestricted access’ means the organisation can access these assets without external input from their parent company or other organisations. The figure would be reported as it was on the final day of the financial year. If the organisation has no access to liquid assets, it should be reported as a zero return. Annual Supplier and Operator Local Authorities and Registered Social Housing Providers Local Authorities and Registered Social Housing Providers Local Authorities and Registered Social Housing Providers Local Authorities and Registered Social Housing Providers Industrial and Self-supply Industrial and Self-supply Industrial and Self-supply Industrial and Self-supply 11 Guidance Heat networks: regular data reporting (draft) Did assets exceed its liabilities at the end of the most recent financial year This is a yes or no response. This is the difference between the value of the assets, liquid assets and fixed assets that the authorised entity owns and controls and the amount of liabilities, debts or obligations, that the authorised entity owes. Annual Supplier and Operator Do you hedge (buying fuel in advance)? If yes, how many months ahead and what percentage volume of costs are hedged? The first part is a yes or no response. A hedging strategy is where an organisation purchases electricity, gas or fuel for delivery on a future date to protect itself from short-term price fluctuations on the cost of wholesale gas or electricity or other input fuel. A hedging strategy is not mandated but an important part of risk management. If yes, a description of how the entity hedges and the number of months’ worth of fuel purchased ahead at the time of providing that data should be provided. Annual Supplier and Operator Local Authorities and Registered Social Housing Providers Local Authorities and Registered Social Housing Providers Industrial and Self-supply Industrial and Self-supply 12 Guidance Heat networks: regular data reporting (draft) Heat network level data The data points in tables 4-8: are to be provided at the heat network level as described in 2.12. General Heat Network Information Table 4: General Heat Network Information data points Data point Data point description Total number of domestic customers This is the total number of domestic customers being supplied by the heat network. Domestic customers are the dwellings purchasing the supply not the total number of consumers or occupants within the dwellings. Reporting Interval Required by the Supplier or Operator Heat Network types data is not required from Consumer types data is not required from Annual Supplier N/A N/A Total number of non- domestic customers This is the total number of non-domestic customers being supplied by the network. Annual Supplier Total number of customers on or using PPMs broken down by: Annual Operator N/A N/A N/A N/A -number of PPMs with at least one smart metering technology -number of legacy PPMs. This is the total number of HCAs within dwellings on the network. Annual Operator N/A N/A Total number of Prepayment meters (PPMs), broken down by smart and legacy meters Total number of Heat Cost Allocators (HCAs) in the 13 Guidance Heat networks: regular data reporting (draft) buildings or on the network, if any. Total number of heat meters domestic customer dwellings, if any. This is the total number of heat meters in a domestic customer dwelling within the heat network. This does not include meters outside of dwellings such as at the energy centre. Total number of customers with smart metering This is the total number of customers with at least one form of smart metering installed in their dwelling, including smart meters. This does not include smart metering outside the building or in the energy centre. Annual Operator N/A N/A Annual Operator N/A N/A Billing Table 5: Billing data points Data point Data point description Reporting Interval Required by the Supplier or Operator Heat Network types data is not required from Consumer types data is not required from Billing frequency This is the frequency that the heat network issues bills to customers on the network, provided as either monthly, quarterly, biannually, annually or other. Annual Supplier Self-supply and Industrial Non-domestic, Microbusiness and Small businesses 14 Guidance Heat networks: regular data reporting (draft) Number of customers by payment method The number of customers broken down by the payment schemes that are listed. Prepayment, direct debit or other. ‘Other’ would include those such as monthly standing order, monthly payment schemes or through cash or cheque. Annual Supplier Self-supply and Industrial Non-domestic, Microbusiness and Small businesses Vulnerability and debt Table 6: Vulnerability and debt data points Data point Data point description The number of consumers in vulnerable situations The number of domestic customers in debt This is the total number of domestic consumers and/or occupants who have been identified as being in a Vulnerable Situation and require Priority Services. This should be the same number tracked within a heat network's Priority Service Register. This is the total number of domestic customers who have met the Debt Trigger, who have charges worth over £200 which have been outstanding for three months or more after the date the bill has been issued. Reporting Interval Required by the Supplier or Operator Heat Network types data is not required from Consumer types data is not required from Annual Supplier Self-supply and Industrial Non-domestic, Microbusiness, and small businesses Quarterly Supplier Self-supply and Industrial Non-domestic, Microbusiness, and small businesses 15 Guidance Heat networks: regular data reporting (draft) The total value of domestic bad debt Provided as a £ this is the total value of bad debt or money owed by customers on the heat network which is unlikely to be repaid or considered unrecoverable. Annual Supplier Self-supply and Industrial Non-domestic, Microbusiness, and small businesses The number of domestic customer self-disconnections The number of domestic customers disconnected for non-payment The number of customers on a repayment plan The number of reconnections due to debt being paid or repayment plan agreed This is the total number of domestic customers who have self-disconnected during this quarter. Quarterly Supplier This is the total of domestic customers who were disconnected by the supplier for unpaid charges or non-payment during this quarter. Quarterly Supplier This is the total number of domestic customers who are on a repayment plan. Quarterly Supplier This is the total number of reconnections that were made of disconnection domestic customers during this quarter. Quarterly Supplier Self-supply and Industrial Self-supply and Industrial Non-domestic, Microbusiness, and small businesses Non-domestic, Microbusiness, and small businesses Self-supply and Industrial Self-supply and Industrial Non-domestic, Microbusiness, and small businesses Non-domestic, Microbusiness, and small businesses Number of meters involuntarily switched to Prepayment meter This is the total number of meters on the heat network that were involuntarily switched, manually or remotely, to Prepayment meters from another type of payment method during this quarter. Quarterly Supplier Self-supply and Industrial Non-domestic, Microbusiness, and small businesses 16 Guidance Heat networks: regular data reporting (draft) Quality of service Table 7: Quality of service data points Data point Data point description Reporting Interval Required by the Supplier or Operator Heat Network types data is not required from Consumer types data is not required from The number of complaints made, broken down by type. These are total number of complaints made during this quarter, including group complaints. Complaints fall under the following categories: Quarterly Supplier Self-supply and Industrial N/A Vulnerability, debt and switching – Complaints related to disconnections or debt management/ repayment and collection and switches to PPM. Quality of service – Complaints related to Interruptions and disruption to the supply of heating, cooling or hot water. Customer service - Any complaints regarding the services offered by the supplier such as the Billing service or complaints process. Pricing - Any complaints related to high prices, affordability or charges and their disputes, or price increases the supplier may have announced, or which have come into effect. Back billing - Any complaints relating to issues on back billing such as incorrect calculations or not issuing bills. Other - Any others that do not fall within the specified categories 17 Guidance Heat networks: regular data reporting (draft) The number of complaints that were group complaints Of the total number of complaints that were made during this quarter, how many were group complaints. Group complaints are those made on behalf of multiple consumers. The number of complaints referred to the Ombudsman These are the total number of complaints that led to a letter being sent signposting the Ombudsman at 8 weeks or after a deadlock situation has been reached. The number of complaints resolved by the end of the next working day This is the total number of complaints that were resolved by the end of the next working day after the complaint was received (Day+1) Quarterly Supplier Self-supply and Industrial Quarterly Supplier Self-supply and Industrial Quarterly Supplier Self-supply and Industrial The number of complaints resolved within eight weeks This is the total number of complaints that were resolved within 8 weeks (56 calendar days) that the complaint was received Quarterly Supplier Self-supply and Industrial N/A N/A N/A N/A Pricing Table 8: Pricing data points Data point Data point description 18 Reporting Interval Required by the Supplier or Operator Heat Network types data is not required from Consumer types data is not required from Guidance Heat networks: regular data reporting (draft) Standing charges Unit rates Connection charges Other charges, for example one-off charges Flat fees Total charges across all domestic customers Total charges across all non-domestic customers A standing charge is a fixed charge that does not change with heat usage. It is charged each day, even on days where no heat is used. All levels of standing charge within a heat network should be reported as £ per day. A unit rate is the rate charged per unit of heat used. All levels of unit rate within a heat network should be reported as £ per kilowatt hour. A connection charge is the amount charged for each new connection. It is a one-off charge independent of usage. All levels of connection charge within a heat network should be reported as £ per customer. Any other charges that are not standing charges, unit rates and connection charges. All levels and types of other charges within a heat network should be reported. A flat fee is the amount charged per day, regardless of the amount of heat used. This is more likely to be applicable to Shared Ground Loop or unmetered networks. All levels of flat fees within a heat network should be reported as £ per day. This is the total amount of standing charges, unit rates, connection charges and other charges received across all domestic customers in the reporting quarter period. (£) This is the total amount of standing charges, unit rates, connection charges and other charges received across all non-domestic customers in the reporting quarter period. (£) 19 Quarterly Supplier and Operator Industrial and Self-supply Quarterly Supplier and Operator Industrial and Self-supply Quarterly Supplier and Operator Industrial and Self-supply Quarterly Supplier and Operator Industrial and Self-supply Quarterly Supplier and Operator Industrial and Self-supply Quarterly Supplier Quarterly Supplier Industrial and Self-supply Industrial and Self-supply N/A N/A N/A N/A N/A N/A N/A Guidance Heat networks: regular data reporting (draft) Charges for customers at reference usage levels Pricing Methodology Types of costs recovered through standing charge Types of costs recovered through unit charge This is the total amount of charges that a reference customer who consumes 6,000 kWh of energy pays in the reporting year period. If there are different levels of charges within a heat network, all charges should be reported. (£) This is a description of how prices are determined in your heat network. For example, you may include your pricing formula, how you set different components of prices, or whether you follow a 'strict cost recovery methodology' or 'cost avoidance methodology'. This is the cost stack of the standing charge - what costs are recovered through the standing charge. You may choose from a list of costs provided. Values are not required. This is the cost stack of the unit rate - what costs are recovered through the unit rate. You may choose from a list of costs provided. Values are not required. Annual Supplier Industrial and Self-supply Non-domestic Annual Supplier and Operator Industrial and Self-supply Annual Supplier and Operator Industrial and Self-supply Annual Supplier and Operator Industrial and Self-supply N/A N/A N/A N/A N/A Types of costs recovered through a flat fee This is the cost stack of the flat fee - what costs are recovered through the flat fee. You may choose from a list of costs provided. Values are not required. Annual Supplier and Operator Industrial and Self-supply Types of costs not passed on These are costs incurred in running the network but not passed on to customers. You may choose from a list provided. Values are not required. Annual Supplier and Operator Industrial and Self-supply 20 Guidance Heat networks: regular data reporting (draft) Funding received Fuel input type Total heat cost Network generation and heat procured Network demand These are revenue streams outside of heat network charges, such as government funding. You may choose from a list provided. Values are not required. This is the main type of fuel used to generate heat in your network if it is not procured from outside. You may choose from a list of options. This is the total heat cost including input fuel cost to generate heat and heat procurement cost in the reporting year period. (£) This is how much heat they have generated and procured in total in the reporting year period. (kilowatt hour) This is the total heat received by customers in the network in the reporting year period. This can be the sum obtained from individual dwelling meters, the sum obtained from building level meters for bulk supply, or estimates if meter readings are unavailable. (kilowatt hour) Annual Supplier and Operator Industrial and Self-supply Annual Operator Industrial and Self-supply Annual Annual Annual Supplier and Operator Industrial and Self-supply Supplier and Operator Industrial and Self-supply Supplier and Operator Industrial and Self-supply Total revenue This is the revenue relevant to heat network activities only in the reporting year period. (£) Annual Supplier and Operator Industrial and Self-supply N/A N/A N/A N/A N/A N/A 21 Guidance Heat networks: regular data reporting (draft) Expenditures (OPEX, CAPEX, REPEX) These are operating expenditure (OPEX), capital expenditure (CAPEX) and replacement expenditure (REPEX) relevant to heat network activities only in the reporting year period. For OPEX, you may include fuel and energy costs, operations and maintenance costs, staff and management costs, billing and customer service costs, and costs on insurance and compliance. If this data is not available at the level of the individual heat network, it can be provided as a total of the portfolio of networks an authorised person has. The reporting of CAPEX and REPEX is optional. (£) Annual Supplier and Operator Industrial and Self-supply N/A 22 Guidance Heat networks: regular data reporting (draft) Appendices Index Appendix 1 Authorisation Condition 6 – Page 24 Provision of Information to the Authority Appendix 2 Data point glossary Page 26 23 Guidance Heat networks: regular data reporting (draft) Appendix 1 – Authorisation condition – Provision of Information to the Authority Condition Title: Provision of Information to the Authority Introduction to condition This condition sets out the requirement on the authorised person to comply with a request from the Authority for information. Given the market segmentation in heat networks and the need to remain flexible in approach to information gathering, it is anticipated that the Authority will use this condition to issue requests for information, including enduring requests. Provision of Information to Authority 1.1. After receiving a request from the Authority for Information that it considers may be necessary or expedient for the performance of any of its functions, the authorised person must give that Information to the Authority. 1.2. The Information provided by the authorised person pursuant to paragraph [6.1] must be provided: 6.2.1. in the Form requested; 6.2.2. in the manner and by the means requested; 6.2.3. at such time, or such intervals of time, as requested; and 6.2.4. in accordance with any applicable guidance issued by the Authority and referred to in the request. 1.3. The authorised person is not required to comply with paragraph [6.1] if the authorised person could not be compelled to produce or give the Information in evidence in civil proceedings before a court. 1.4. The Authority’s power to request Information under this condition is additional to its powers to call for Information under or pursuant to any other condition or the Regulations. Provision of reasoned comments to the Authority 1.5. After receiving a request from the Authority for reasoned comments on the accuracy and text of any Information which the Authority proposes to publish under 24 Guidance Heat networks: regular data reporting (draft) regulation 12 of the Regulations, the authorised person must give such comments to the Authority when and in the Form requested. 25 Guidance Heat networks: regular data reporting (draft) Appendix 2 – Data point glossary Definitions A2.1 Complaint - an expression of dissatisfaction about the standard of service, action or inactions of the authorised person, or those acting on its behalf, where: (a) the dissatisfaction arises in direct response to the carrying out of a regulated activity by the authorised person, or those acting on its behalf; (b) one or more Relevant Consumers are affected; and (c) a response is explicitly or implicitly required or expected to be provided thereafter. A2.2 Debt - means, where Charges have been outstanding for three months or more after the date the bill has been issued, and Outstanding Charges are more than the amount specified by the Authority for these purposes and the Consumer is not on, or transitioning, to a repayment plan; A2.3 Direct debit - refers to customers who pay a variable direct debit on a recurring basis A2.4 Domestic customer - heat network customer supplied or requiring to be supplied by means of a relevant heat network at a Domestic Premises A2.5 Non-domestic customer - a heat network customer supplied or requiring to be supplied by means of a relevant heat network at a Non-Domestic Premises but excludes such a heat network customer insofar as they are supplied or require to be supplied at premises other than Non-Domestic Premises A2.6 Prepayment meter - refers to customers who pay for their energy as they go by pre-payment meter A2.7 Reconnection - This is when you restore a supply of heating, cooling or hot water to customers who had previously been disconnected. A2.8 Repayment plan – A repayment plan is an agreement that allows customers to pay off their debt in instalments over time. A2.9 Self-disconnection - means when a Domestic Consumer uses a Prepayment Meter and experiences an interruption to their supply of heating, cooling or hot water because the credit on the meter has been exhausted A2.10 Shared Ground Loop - Where 2 or more properties are heated by individual ground source heat pumps connected to it. A2.11 Vulnerable customer - means where the personal circumstances and characteristics of a person create a situation where he or she is:(a) significantly less able than a typical person to protect or represent his or her interests; and/or (b) significantly more likely than a typical person to suffer detriment or that detriment is likely to be more substantial; 26 --- Decision Heat networks regulation: regular data reporting guidance Publication date: 10 March 2026 Team: Email: Heat Networks HeatNetworksRegulation@ofgem.gov.uk This document sets out our decision following consultation on draft guidance for regular data reporting guidance which was published on 18 November 2025. It provides a summary of responses to each question in the consultation and the details of our decisions. We have published an updated version of the Heat networks regulation: regular data reporting guidance alongside this decision. Decision Heat networks regulation: regular data reporting guidance © Crown copyright 2026 The text of this document may be reproduced (excluding logos) under and in accordance with the terms of the Open Government Licence. Without prejudice to the generality of the terms of the Open Government Licence, the material that is reproduced must be acknowledged as Crown copyright and the document title of this document must be specified in that acknowledgement. This publication is available at www.ofgem.gov.uk. Any enquiries regarding the use and re-use of this information resource should be sent to psi@nationalarchives.gsi.gov.uk. 2 Decision Heat networks regulation: regular data reporting guidance Contents Executive summary ............................................................................................. 4 Introduction ........................................................................................................ 5 Context and related publications .............................................................................. 5 Decision-making stages ........................................................................................... 5 Our decision ............................................................................................................ 5 1. Guidance on data reporting ............................................................................. 6 Question analysis .................................................................................................... 6 Ofgem response ...................................................................................................... 9 3 Decision Heat networks regulation: regular data reporting guidance Executive summary Ofgem has been appointed as the regulator for heat networks and since 27 January 2026, heat networks must now comply with consumer protection regulations as part of their authorisation conditions. The aim of the new regulatory regime is to deliver good outcomes for heat networks customers. We want to ensure heat network customers are treated fairly, receive clear and transparent information about their heat supply, a reliable service and fair prices. In developing the detailed authorisation conditions underpinning these outcomes, we are introducing a framework that aims to be proportionate, cost effective and drives improvements in consumer outcomes, while delivering a stable regime which supports investment. To provide oversight of heat network compliance with the new regulations, we are introducing data reporting that will be our primary source of intelligence from the heat network sector. Our previous publications have helped develop our work on the monitoring regime. Our approach to monitoring is designed to enhance our understanding of the sector as we take on our new regulatory role and to assist us in shaping our approach to regulating this sector. It will also support our approach to compliance, where we will work with the sector to embed the new consumer protection requirements. A common piece of feedback from previous consultations has been to introduce guidance to support industry in meeting their requirements. This consultation was to ensure the sector and the regulated authorised persons had an opportunity to feedback on the draft guidance that aims to support their ongoing data reporting requirements. The data reported during the first year of regulation will be important for Ofgem to develop a greater understanding of the sector which we will use to refine and strengthen the framework. We want our requests for data from the market to be proportionate and will only ask for data that we consider necessary. As our knowledge of the heat network market grows, we will continue to review data requirements to ensure it remains proportionate. The monitoring framework forms part of our engagement with the sector to measure compliance with the authorisation conditions. Where there is non-compliance, our aim is to have an open and supportive dialogue with heat networks. We encourage self- reporting of issues and the submission of available data even if it will mean an incomplete data set through our digital service to support this transparent approach. For more information on our approach to engagement with the sector please see our heat networks compliance approach. 4 Decision Heat networks regulation: regular data reporting guidance Introduction This is the decision to the consultation “Heat networks regulation: data reporting guidance” which was open from 18 November 2025 to 12 January 2026. The consultation presented a first version of guidance for data reporting for the sector to provide feedback on. The consultation outlined our intention to collect the data points within the guidance and for existing heat networks to backdate those data points to April 2026. Context and related publications Following regulatory commencement, the general authorisation conditions which the regularly reported data points are based on, came into effect. Authorised persons should read the guidance alongside the authorisation conditions to understand their ongoing data reporting obligations, as well as the other available guidance. Decision-making stages We received 31 responses to the consultation from a range of stakeholders including trade associations, consumer groups and heat network suppliers and operators. We have reviewed all the responses and provide a summary of these here. We have reflected feedback in the updated version of guidance which has been published alongside this decision. Our decision In the consultation we provided descriptions of the data points, alongside information about which authorised entities would not be required to provide certain data, and whether the supplier or operator is required to provide it in the event they are separate entities on a heat network. We have updated the descriptions based on feedback received during the consultation period and additional stakeholder engagement. The consultation also covered our approach to backdating. We proposed that, once registration was complete and monitoring functionality introduced to the digital service, heat networks would be required to provide data from the period beginning April 2026. We acknowledge feedback to the consultation that some heat networks will not be in a position to provide all the necessary data from April 2026. We will still request all data from April 2026 and our preference is for heat networks to provide a full submission. However, initially where heat networks do not have all the data available, they should still provide a partial submission. Going forward, as we continue to gather data on the market through our monitoring regime and other sources of intelligence, we will review both our approach to monitoring and future iterations of data reporting guidance. 5 Decision Heat networks regulation: regular data reporting guidance 1. Guidance on data reporting We consulted on draft guidance including the enduring reported data points and their descriptions, as well our approach to backdating data. We have further developed the data descriptions following feedback from the sector. We have sought to provide additional detail to clarify issues raised by stakeholders in their responses. Stakeholders indicated issues meeting the requirements in time given the changes needed to their systems. We have updated our approach to backdating and what our expectations are for the first year of reporting. Stakeholder feedback often asked for clarity to help ensure compliance with the requirements and what would happen in the event of non-compliance. We have provided some detail our approach to compliance with the data reporting requirements in this document, but we also recommend reading our published compliance approach. Question analysis Q1. Do you agree that the descriptions of the data points are clear? Are there any data points where we could provide a clearer description? Table 1: Response summary for consultation question 1 Response Number of responses Percentage Agree Partially agree Disagree Not answered Comments 9 17 5 0 28 29% 55% 16% 0% 1.1 The majority (55%) partially agreed and had recommendations or questions about the data descriptions within the guidance. Nine respondents agreed and five disagreed. Of the 31 stakeholders who answered the question, 28 provided comments. 1.2 Several stakeholders requested that the glossary should be expanded to include additional definitions or more detailed descriptions of terms used for data points. 6 Decision Heat networks regulation: regular data reporting guidance Terms that could be added to the glossary included smart metering, heat Cost allocators, bad debt, non-domestic customers and repayment plans. 1.3 Some stakeholders asked whether estimated data or a best indication of data could be submitted, including scenarios such as heat networks being unmetered. 1.4 Some respondents who agreed or otherwise thought the data points were clear still provided feedback to improve the data point descriptions. 1.5 Stakeholders supported the format of the data points being spilt between the tables. Some stakeholders commented whether the data points that could be submitted as having not changed since the last submission or which ones would not be provided by unmetered heat networks be included within the tables. 1.6 Two small heat networks who disagreed flagged that they would struggle to gather the data set as a whole. Two other respondents also highlighted that guidance and the descriptions could be clearer for heat networks that are a part of blocks of flats. 1.7 One respondent noted that the number of self-disconnections is not possible on all Pay As You Go (PAYG) systems. Whilst snapshots could be available, the number of all instances of self-disconnections could not be provided until development from existing PAYG system providers. 1.8 Our response is on page 9. Q2. Do you agree with the requirement to provide data back to April 2026 following registration for existing networks? If not, what would be a reasonable start date to collect data from and please state what factors would prevent your organisation from gathering and holding onto this data from April 2026? Table 2: Response summary for consultation question 2 Response Number of responses Percentage 39% 29% 29% 3% 12 9 9 1 27 Agree Partially agree Disagree Not answered Comments 7 Decision Heat networks regulation: regular data reporting guidance 1.9 The highest number of responses agreed with data being backdated to April 2026 following registration. An equal number of responses either partially