Feed-in Tariffs: guidance for suppliers
Summary
Ofgem has updated its FIT supplier guidance (Version 18) to reflect the government's mandated transition from RPI to CPI inflation indexation for FIT tariff adjustments, following the January 2026 consultation response. The update also includes a revised contact email for the RE Compliance Team.
Why it matters
The RPI-to-CPI switch systematically reduces future FIT payments to generators, since CPI typically runs 0.5-1.0 percentage points below RPI. This is a quiet transfer of value from small-scale generators to suppliers and ultimately to consumers funding the FIT levy.
Key facts
- •Version 18 of FIT supplier guidance, updated 1 April 2026
- •Transition from RPI to CPI inflation indexation for FIT tariff adjustments
- •Implements DESNZ consultation response published 28 January 2026
- •FIT scheme is closed to new applicants but continues to pay existing generators for their tariff lifetime (up to 25 years)
Timeline
Areas affected
Related programmes
Memo
Feed-in Tariffs: guidance for suppliers | 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: Feed-in Tariffs: guidance for suppliers Publication type: Guidance Publication date: 23 May 2025 Last updated: 1 April 2026 Scheme name: FIT Print this page This guidance is for all licensed electricity suppliers to ensure the effective administration of their duties under the Feed-in Tariffs (FIT) scheme. Version 18 incorporates updates across several sections, including revisions to FIT tariff adjustments to reflect the transition from RPI to CPI inflation indexation, in line with the Government’s Changes to Inflation Indexation in the Feed‑in Tariffs (FIT) Scheme consultation response published on 28 January 2026. This version also includes an updated contact email address for the RE Compliance Team. Main document Feed-in Tariffs: guidance for licensed electricity suppliers [PDF, 1.24MB] Print this page Close