Together, Sprint and T-Mobile would have had control of almost 50% of the prepaid market, according to opponents of the deal.
If the deal is approved by the FCC, which seems likely, and the Justice Department also concurs, both companies will have until July 29th to close the transaction unless it is extended again.
FCC Chairman Ajit Pai, a Republican, came out in favor of the combination after the companies offered several concessions, including selling Sprint's Boost Mobile prepaid cell service. The new Boost could buy network access from T-Mobile for at least six years.
The two companies also promised a rapid build out of its 5G network, seeking to cover at least two-thirds of the USA population with download speeds that exceed 100 megabits per second.
T-Mobile and Sprint also "offered specific commitments regarding the rollout of an in-home broadband product, including to rural households", Pai said. In that case, the carrier will use the 200MHz chunk of spectrum in the 28GHz and 39GHz bands.
In subsequent tweets, T-Mobile CEO Legere and Sprint chairman Marcelo Claure each disputed the report with Legere calling the premise "untrue".
A sign for a T-Mobile store is seen in Manhattan, New York, U.S., April 30, 2018. Furthermore, T-Mobile and Sprint promise that 90 percent of Americans will have access to mobile broadband service at speeds of at least 100 Mbps and 99 percent will have access to speeds of at least 50 Mbps.
T-Mobile also says it wants to make sure the vast majority of rural areas of the USA will be able to use its 5G network.
"This 5G network would also reach deep into rural areas, with 85% of rural Americans covered within three years and 90% covered within six years", Pai said.
Pai released a statement saying that because T-Mobile and Sprint have committed to covering nearly the entire country with 5G over the next three years (97% of the population), increasing buildout of their mid-band spectrum holdings, creating another home broadband choice for rural customers who don't have many, and selling off Boost, Sprint's prepaid brand, he is willing to recommend an approval. That number will expand to 28 million eligible households in six years, including 5.6 million rural households.
Legere repeated earlier commitments to not raise prices on its current plans - including 5G plans - for three years after the merger is complete.
Sprint to say goodbye to Boost Mobile?
Finally, T-Mobile has reitereated its commitment to pricing post-merger.
If approved, it would reduce the number of major US wireless telecom carriers from four to three.
"We'll work to find a serious, credible, financially capable and independent buyer for all the assets needed to run - and grow - the business", Legere writes.
T-Mobile has about 80 million customers and Sprint about 55 million customers.
A key federal regulator says he plans to approve wireless carrier T-Mobile's $26.5 billion takeover of rival Sprint, a crucial step for the deal's approval.
"Two of the FCC's top priorities are closing the digital divide in rural America and advancing United States leadership in 5G, the next generation of wireless connectivity", said Pai.