RIIO-2 regulatory performance data: 2025
- Publication type:
- Data
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This data file provides Ofgem's view of network companies' regulatory financial performance during the fourth year of RIIO-2 for Gas Distribution, Gas Transmission & Electricity Transmission (GD&T) companies & second year for Electricity Distribution (ED) companies.
Return on Regulated Equity (RoRE) is Ofgem’s measure of the financial return achieved by shareholders from a licensee during a price control period. RoRE is calculated and reported annually through the Regulatory Financial Performance Report (RFPR). As required by Ofgem, each licensee published its RFPR for the relevant period on its website in September 2025. This data file consolidates those individual RFPR publications, providing a comprehensive view of actual performance through 2024/25 and forecast data through the end of the current price control period i.e. 2025/26 for GD&T and 2027/28 for ED. The file allows the user to switch between actual and notional gearing, and between cumulative RIIO-2 to date and the full RIIO-2 period. To switch, go to the ‘RoRE by sector 2024-25’ and ‘RoRE by licencee 2024-25’ tabs and use the drop-down options in cells B4 and B5.
RoRE reflects how companies’ allowed returns are influenced by differences between actual and planned expenditure, incentives and finance costs (interest and tax). However, certain companies significantly outperformed their allowed finance costs, primarily due to how high inflation interacts with the debt allowance methodology. Where inflation is higher than a long run assumption (typically 2%) some companies can outperform. Importantly, this effect is symmetric, had inflation dropped below the long run assumption by the same magnitude, companies would have underperformed by an equivalent amount.
Recognising the impact of recent high inflation, Ofgem has updated its approach. Following consultation in August 2023, the RIIO‑3 Final Determination (4 December 2025) introduced adjustments to the cost of debt methodology for Gas Distribution, Gas Transmission and Electricity Transmission to reduce unwarranted out‑ or under‑performance driven by inflation. Ofgem will also propose equivalent reforms for Electricity Distribution in ED3, ensuring a more stable and predictable regulatory regime for consumers.