(Pocket-lint) - T-Mobile is green-lighting its 5G network in the US just in time for the holidays.

During a live stream with T-Mobile CEO John Legere and COO Mike Seivert, the so-called "un-carrier" revealed that its 5G mobile network will officially go live on 6 December - with a caveat, of course. It is dependent on T-Mobile’s merger with Sprint, which recently passed a major hurdle by receiving FCC approval on Nov. 5. However, there are still attorneys generals from 18 different states in the US who have expressed concern.

They fear the merger will harm competition for consumers. But, if the merger goes through, T-Mobile promises that 200 million customers in 5,000 cities and towns will have access to 5G network speeds immediately, with no extra charges or changes required. You will need specific 5G smartphones, however, in order to take advantage of the improved 5G speeds from T-Mobile/Sprint. 

T-Mobile’s new 5H network is using a low-band spectrum for its 5G network, versus the millimeter-wave based network that Verizon and AT&T are using for their 5G networks. This difference means T-Mobile’s network might have slightly slower speeds, but it might also be better at penetrating buildings and tree cover compared to Verizon and AT&T’s 5G networks. Pocket-lint has yet to them.

Currently, there are only two phones capable of using T-Mobile’s 5G network: the Samsung Galaxy Note 10 Plus 5G and the OnePlus 7T 5G McLaren Edition. But we suspect more phones due in 2020 will try to work with T-Mobile's network. 

Writing by Maggie Tillman.