T-Mobile US today reinforced its 5G network lead in the U.S. with a low-band network that covers 300 million people and a mid-band network that covers more than 150 million people.

The operator beat its low-band 5G network goals by six months and remains on track to reach at least 200 million people with mid-band 5G coverage by the end of the year. 

“Last year, when we said we’d cover 300 million people with 5G by the end of 2021, people thought we were crazy. Now, we’ve blown by that goal six months ahead of schedule,” CEO Mike Sievert said in a statement.

T-Mobile’s Ultra Capacity 5G network generates average download speeds of 325 Mb/s, peaking at 1 Gb/s, according to the operator. The entire 5G footprint spans 1.6 million square miles, a 5G coverage area that’s roughly double that of AT&T and four times larger than Verizon, the operator claimed.

The carrier previously said its mid-band 5G network will cover 250 million people by the end of 2022 and 285 million people by the end of 2023. That would effectively cover about 90% of the U.S. population. 

The low-band network plays a significant role in T-Mobile’s push to increase its market share in rural areas. The operator wants to jump from a rural market share in the low teens today to about 20% by 2025.

The operator expects the twilight of 4G LTE to hit in 2023, harkening the arrival of the 5G era.

The latest milestones also underline how quickly T-Mobile made use of the mid-band spectrum and additional customer base it gained through its April 2020 merger with Sprint. 

Part of T-Mobile’s 5G network upgrade involves the integration of thousands of former Sprint cell sites and the decommissioning of many others. The operator previously said it will decommission up to 8,000 macro cell sites by the end of this year and it plans to take 35,000 macro sites offline by the end of 2022. That decommissioning effort will generate about $3 billion in run-rate synergies alone, according to T-Mobile. 

The operator now expects total synergies generated from the deal to surpass $70 billion, up 62% from the $43 billion it originally outlined three years ago. T-Mobile said it will have at least 85,000 active macro radio access network (RAN) sites and 50,000 small cells when its network upgrade is complete.

Neville Ray, T-Mobile’s president of technology, earlier this year, said the operator will head into 2022 with about 60 megahertz of untapped 2.5 GHz spectrum nationwide and 40 megahertz of C-band spectrum in major U.S. markets.

The operator also holds licenses for millimeter-wave spectrum, but there’s no indication it plans to increase deployments on those holdings at any significant level in the next few years. The top layer of T-Mobile’s three-layer cake 5G network strategy is and will effectively remain unbaked or at least unfrosted.