In a boost to the Liberty Global, Telefónica and InfraVia joint venture’s plans to compete with BT Openreach on a more robust basis in the UK’s full-fibre arena, the Competition and Markets Authority (CMA) is to fast-track to Phase 2 the plans by broadband firm Nexfibre to acquire Substantial Topco and its subsidiary undertakings, including independent broadband providers (altnets) Brsk, YouFibre and, most significantly, Netomnia.
The acquisition – for which the Netomnia element alone is valued at £2bn – was first announced in February 2026, in a deal that Nexfibre claimed would unlock a value of £3.5bn, creating sustainable, scaled network competition and enhanced wholesale choice in the UK.
Founded in 2019 and owned by investors Advencap, DigitalBridge and Soho Square Capital, Substantial Group is expected to have more than 3.4 million fibre premises and over 500,000 customers by completion of the deal. Substantial Group’s fibre network, Netomnia, is regarded as the UK’s fourth-largest full-fibre network and second-largest UK altnet.
Netomnia undertook a merger with fellow altnets YouFibre and Brsk in the summer of 2024, and the company ended 2024 with 2.08 million premises serviceable, adding 1.27 million in the year in which it made an acquisition that added 255,000 in the final quarter. It had 238,000 premises connected in the 12-month period, representing 171,000 in a year and 48,000 in Q4 2024. Together with YouFibre and Brsk, Netomnia has had a target to reach five million UK premises serviceable by the end of 2027.
Even though the footprint of the UK’s altnets has grown strongly over the past two years, analysts have warned for some time that companies in the sector were facing increased commercial pressure that could result in a consolidation wave.
Commenting on the deal in February 2026, Substantial Group CEO Jeremy Chelot said the “landmark” transaction with Nexfibre – in which Virgin Media O2 has a major holding – represented a natural evolution of the UK’s fibre market. “Consolidation has been inevitable, and this deal creates the scaled, sustainable platform needed to drive genuine wholesale competition,” he said.
“Importantly, our retail brand, YouFibre, will remain post-close, ensuring our customers continue to receive the same trusted service they know today, while benefiting from the financial strength and infrastructure scale this combination delivers. This is about building a stronger future for UK fibre.”
On 11 June, Nexfibre and Substantial requested the CMA to make a fast-track reference for an in-depth investigation of the takeover at Phase 2.
After studying their proposal, the CMA concluded that the conditions to accept a fast-track reference request under section 34ZF(3) of UK competition law have been met, and that it would be appropriate to accept the fast-track reference request and proceed to a Phase 2 investigation. The statutory deadline for Phase 2 of the investigation is 15 December.
Offering rationale for hastening the procedure, Nexfibre said its acquisition of Netomnia would be a landmark deal for the UK fibre market, moreover underpinning the country’s ambitions for the future of its digital economy. It added that it was important that the Competition and Markets Authority (CMA) had the analysis and information it needs to reach a timely decision.
Furthermore, the provider warned that the current UK altnet market remains fragile, and that the window to secure long-term competition was narrowing. It argued that approving the acquisition would establish wholesale competition to BT Openreach, driving greater choice, better quality and improved value for customers, while supporting a faster transition to full-fibre. The choice, it stressed, was clear: establish a strong competitive framework for next-generation broadband, or maintain what it called the monopolistic status quo holding the country back.
“We requested a fast-track to Phase 2 to get to the right answer faster, ensuring due process while recognising urgency,” said Nexfibre CEO Rajiv Datta. “We look forward to continuing our constructive engagement with the CMA.
“This deal would create the scaled, sustainable alternative to the BT Openreach monopoly, something the UK market still lacks. Every day of delay reinforces the incumbent’s advantage and slows the progress of genuine competition.”
Yet Nexfibre’s rivals have warned that the takeover raises substantial questions about the competitiveness of the UK’s communications market.
Commenting on the CMA’s move, Simon Holden, CityFibre CEO, said: “VMO2/Nexfibre’s planned acquisition of Netomnia would remove a successful challenger and reduce choice for consumers. With 80% overlap between the two networks, the deal raises significant questions, and the CMA is right to take an in-depth look at its impact on UK digital infrastructure and the competition that policymakers, regulators and the altnets are working so hard to establish.”
