T-Mobile US lit mid-band 5G coverage in 81 additional cities across the US, as it pressed ahead with a plan to put Sprint’s legacy 2.5GHz spectrum to work in thousands of locations by end-2020.

Its latest launches span 18 states, extending coverage to major markets including Atlanta, Dallas, Winston-Salem and Washington DC. The move builds on earlier deployments in Chicago, Houston, Los Angeles, New York City and Philadelphia, and puts T-Mobile’s next-generation 2.5GHz footprint well above that achieved by Sprint prior to the pair’s merger.

Though the operator already offers nationwide 5G coverage on its low-band 600MHz spectrum, it noted the addition of 2.5GHz enables it to deliver faster data rates, with a peak of close to 1Gb/s and typical speeds of 300Mb/s.

T-Mobile said is deploying the spectrum on approximately 1,000 sites per month as it works towards covering thousands of cities by the end of the year.

During its Q2 earnings announcement, T-Mobile president of technology Neville Ray predicted mid-band spectrum would be a “game changer” for its 5G goals.