Markets data definitions
Summary
Ofgem has published a data definitions glossary to standardise terminology across its Markets data collections from suppliers. The document is an XLSX reference sheet explaining terms used in data requests. It does not introduce new requirements or override existing licence conditions.
Why it matters
Administrative housekeeping. Suppliers already submit this data; this standardises the language around it. No cost, rule, or market structure changes.
Key facts
- •Published 2 April 2026 as a transparency document
- •Covers Markets data collections terminology only
- •Does not override licence conditions or collection-specific guidance
- •Contact: MarketsDMO@ofgem.gov.uk
Areas affected
Memo
Markets data definitions | Ofgem Please enable JavaScript in your web browser to get the best experience. BETA This site is currently in BETA. Help us improve by giving us your feedback . Close alert: Markets data definitions Publication type: Transparency document Publication date: 2 April 2026 Topic: Financial resilience Print this page Share the page Share on Facebook Share on Twitter Share on LinkedIn High-level data definitions to help suppliers and Ofgem teams interpret data requests consistently. They support clarity and do not replace guidance. Purpose of the Markets data definitions The Markets Data Definitions are designed to help users understand and interpret the terminology used in Markets data collections. They aim to: explain key data terms used across Markets collections support consistent interpretation of data requests improve clarity and comparability of information submitted to Ofgem These definitions act as a supporting reference. They complement—not replace—the guidance for individual data collections. Using the definitions with data collection guidance Always use the Markets data definitions together with the guidance, templates and instructions published for each data collection. The definitions do not introduce new requirements. They should not be used alone when preparing or submitting data to Ofgem. Important information The definitions are high level and explanatory. They do not override licence conditions, statutory guidance or the specific instructions for an individual data collection. If there is any difference between a definition and collection specific guidance, the collection specific requirements always take precedence. Governance and updates All definitions are reviewed and approved through Ofgem’s Markets data governance processes before publication. The dictionary will be updated periodically, based on regulatory changes and user feedback. Contact Please contact MarketsDMO@ofgem.gov.uk for further information. Documents Markets data definitions [XLSX, 48.20KB] Print this page Share the page Share on Facebook Share on Twitter Share on LinkedIn Close