Vodafone and Three have been cleared to create the UK’s biggest mobile operator after committing to address concerns around network upgrades and price hikes. The proposed £16.5 billion merger (about $20.9 billion) was approved by the Competition and Markets Authority (CMA) on Thursday following months of regulatory scrutiny, and is expected to be completed in the first half of 2025.

“Having carefully considered the evidence, as well as the extensive feedback we have received, we believe the merger is likely to boost competition in the UK mobile sector and should be allowed to proceed – but only if Vodafone and Three agree to implement our proposed measures,” Stuart McIntosh, chair of the inquiry group leading the antitrust investigation, said in a statement.

The approval was subject to both companies signing binding commitments to invest billions into expanding their combined 5G network over the next eight years. The agreement also requires the new entity to cap some mobile tariffs and offer preset contractual terms to mobile virtual network operators for three years, addressing previous CMA concerns that the merger could harm competition and lead to higher prices for customers.

The plan to combine two of the country’s top four mobile operators was first announced in 2023, and will create a network with 27 million customers once complete. Vodafone will own 51 percent of the merged entity, and is expected to buy out the remaining 49 percent after three years. The deal follows similar large-scale mergers between companies like Orange and T-Mobile in 2010, and Virgin Mobile and O2 in 2021.