The merger was officially cleared in February and has today been completed following legal hurdles.

“During this extraordinary time, it has become abundantly clear how vital a strong and reliable network is to the world we live in. The New T-Mobile’s commitment to delivering a transformative broad and deep nationwide 5G network is more important and more needed than ever and what we are building is mission-critical for consumers,” said Mike Sievert, president and CEO.

“With this powerful network, the New T-Mobile will deliver real choice and value to wireless and home broadband customers and double down on all the things customers have always loved about the Un-carrier. T-Mobile has been changing wireless for good — and now we are going to do it on a whole new level!”

It was John Legere, CEO since 2012, who helped shape T-Mobile’s image into one of a disruptor, undercutting its rivals on price and customer friendly launches under the Un-carrier branding. He took the company from comfortably fourth in the market behind Sprint to the T-Mobile that has just acquired it.

For the merger to be allowed, T-Mobile has had to make some big promises including promising low-band 5G coverage for 99% of the US within six years. Within the same time frame it has also aimed to deliver an in-home wireless internet service.