UScellular has confirmed that it will sell a portion of its spectrum assets to AT&T for $1 billion.

The announcement of the sale comes weeks after UScellular agreed to a similar $1bn deal with Verizon.

According to UScellular, the sale forms part of its strategy to monetize the spectrum that was not included in the proposed $4.4 billion sale to T-Mobile.

That particular deal will see T-Mobile acquire a significant chunk of UScellular's operations, including its customer base and around 30 percent of the company's wireless spectrum.

"We are pleased with the significant value that will be realized in the various transactions recently announced," said Laurent C. Therivel, president and CEO. 

"This agreement adds a fourth mobile network operator, in addition to T-Mobile, to the list of those whose subscribers will benefit from the sale of our spectrum licenses.  As with the other mobile network operators, we are confident that AT&T can put it to productive use in communities throughout the US Furthermore, the terms of the agreement will ensure that there will be continued, uninterrupted service for UScellular customers in the interim."

As part of the agreement, AT&T will snap up 1,250 million MHz-Pops of 3.45 GHz and 331 million MHz-Pops of 700 MHz B/C block licenses.

Some of the assets are owned by third parties, notes UScellular, with those licenses covering approximately 15 percent of the total MHz-Pops represented in the announced transaction.

After announcing spectrum deals with all three of the 'Big 3' US carriers, UScellular said it will retain 1.86 billion MHz-Pops of low and mid-band spectrum and 17.2 billion MHz-Pops of mmWave spectrum, with the substantial majority of retained value in the C-band spectrum.

"The C-band licenses have a number of attributes that we believe are favorable to their long-term value.  First, our C-band licenses are positioned in an attractive mid-band frequency that can deliver outstanding speed and capacity," said Therivel. 

"Second, there is a substantial 5G ecosystem of equipment vendors and existing infrastructure that uses C-band.  Finally, they have a lengthy build-out timeline, with first and second build-out dates of 2029 and 2033, respectively. This provides ample time and optionality for us to either monetize or deploy the spectrum in the future.  We will continue to look for ways to opportunistically monetize the C-band, as well as the other remaining spectrum."

Regional provider UScellular serves more than 4.5 million mobile customers across 21 US states.

The company, which claims to be the seventh-largest wireless provider in the US, urged the Federal Communications Commission (FCC) last month to approve its $4.4bn asset sale to T-Mobile, noting that the deal is essential to the company's future.

UScellular said it has "consistently lost subscribers in recent years," while the market has ramped up in competitiveness from both traditional wireless providers and cable companies.

This has led UScellular to scale back its 5G investment as it instead looks to ease its debts.