SOUTHERN GAS NETWORKS PLC

(LEGAL IDENTIFIER NUMBER: 549300SPX8573VZ2SK79)

SGN Board seeks permission to bring an appeal against Ofgem's RIIO-GD3 Final Determination to the Competition and Markets Authority (CMA)

The Board of Directors at Southern Gas Networks plc and Scotland Gas Networks plc (together, "SGN") has requested the CMA to bring an appeal on elements of the RIIO-GD3. The licence was published by Ofgem on 3 February 2026 and was based on Ofgem's Final Determination published on 4 December 2025.

SGN is a leading engineering organisation that designs, builds, operates and maintains energy systems of today and tomorrow.

SGN's GD3 Business Plan set out the investment programme required, in our role as duty holder, to operate a safe and reliable gas network and to maintain security of supply for six million homes and businesses across south London, the south of England and Scotland. Our plan, which was the result of extensive stakeholder engagement, protected customers' interests by ensuring essential investment in safety, resilience and reliability, while keeping affordability firmly in view.

SGN and Ofgem held constructive discussions but have been unable to agree on a number of grounds prior to yesterday's deadline and therefore we have requested that the matter pass over to the CMA.  

While the CMA process is ongoing, SGN remains committed to delivering operational excellence and outstanding service for all our customers.

For further information, please contact:

Felix Fletcher

Director of Corporate Finance and Treasury

Nexus

25 Farringdon Street,

London,

EC4A 4AB

+44 (0)7738 699 302

[email protected]