Joshua Goldman/CNET

T-Mobile promised its nationwide 5G network was coming before the end of the year, and now we have a launch date: Dec. 6.

In a webcast announcing its latest "un-carrier" moves designed to get its Sprint merger approved, CEO John Legere and COO Mike Seivert revealed that T-Mobile will be launching its new, faster network will cover over 5,000 cities and towns with the signal able to work indoors as well as outside.

The company previously announced that the Samsung Galaxy Note 10 Plus 5G and the OnePlus 7T Pro 5G McLaren edition will be its first two phones capable of tapping into this new network.

No pricing was revealed for the devices, but in a call with reporters after the event, Seivert said that T-Mobile's existing plans will be able to access 5G, no changes or extra charges needed.

T-Mobile previously launched 5G in six cities using millimeter-wave, a high-frequency technology that is currently used by Verizon and AT&T for their 5G networks. While great for speed, this network struggles to cover large areas or penetrate trees or buildings to provide service indoors.

The new network, using what is known as low-band spectrum, may not be as fast as millimeter-wave but offers significantly better coverage and will be built on top of the company's 4G LTE network to offer faster speeds compared to 4G.

The new Samsung and OnePlus phones, however, will only work on this low-band network and Sprint's midband 5G spectrum (should that deal be approved), as devices that connect to all the different types of 5G networks won't be available until 2020.

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Originally published Nov. 7, 7:26 a.m. PT.

Update, 7:44 a.m. PT: Adds details on plans and Sprint.