Energy licence modification appeals 2026

Published on 10 April 2026, as required by Rule 13 of the Energy Licence Modification Appeals: Competition and Markets Authority Rules (CMA70). Any changes to the timetable will be published on this page.

9 September 2026: Following representations from the parties, the CMA decided on 4 September 2026 to extend the deadline for the determination of the appeals by one month to 31 October 2026.

14 August 2026: The CMA has published a summary of its provisional determinations in the Energy Licence Modification Appeals 2026. The full provisional determinations will be issued to the parties and intervener.

20 May 2026: On 8 May 2026, the appellants submitted a joint reply to the response from the Gas and Electricity Markets Authority (GEMA), Ofgem’s governing body, to the notices of appeal in relation to Ongoing Efficiency.

On 12 May 2026, Southern Gas Networks plc and Scotland Gas Networks plc (SGN) submitted a reply to GEMA’s response to SGN’s notice of appeal.

29 April 2026: On 23 April 2026, GEMA responded to the appellants’ notices of appeal.

29 April 2026: On 23 April 2026, the CMA received an application for permission to intervene from Citizens Advice. On 28 April 2026, the CMA issued its decision on the application allowing Citizens Advice to intervene in relation to the grounds of appeal relating to Ongoing Efficiency.

31 March 2026: The CMA has appointed a group of 3 panel members to determine the appeals.

31 March 2026: The CMA has granted permission to appeal on all grounds pleaded by the following appellants:

Permission is granted subject to the condition that the grounds of appeal relating to GEMA’s assessment of Ongoing Efficiency, which each of the appellants has raised in their respective notices of appeal, be considered together.