T-Mobile saw continued customer growth in the first quarter, adding a combined 1.3 million net customers across its phone and internet businesses, the company said during its Q1 earnings call Thursday.

The carrier reported 538,000 net phone additions, the metric used by the industry to denote success and dependable revenue. T-Mobile said its 5G network reaches 98% of Americans and that its higher-speed “Ultra Capacity” 5G network now covers 275 million people, with a goal to reach 300 million by the end of the year.

It gets increasingly difficult to reach the last slices of the American population given geography constraints, said Ulf Ewaldsson, T-Mobile’s executive vice president of network. “I would say it’s about three times harder for every 10 [thousand people] you add,” he said.

Ewaldsson noted that T-Mobile has 150MHz of dedicated midband 5G spectrum, and as the carrier shifts more frequency from 4G LTE to 5G, it’ll end the year with over 200MHz on midband. “We’re very confident that we’ll reach [our year-end goal] with the build plan we have today,” he said. 

During the call, CEO Mike Sievert touted the progress T-Mobile has made in the three years since the carrier merged with Sprint, in April 2020, a merger that was in the works for three years before getting regulatory approval. Sievert said the six-year journey would enable the company “to leapfrog AT&T and Verizon from being last place in the LTE era to first place in the 5G era.”

Sievert also touted the carrier’s new pair of slightly pricier phone plans, called Go5G and Go5G Plus, which add mobile hotspot data and roaming perks on top of the company’s existing Magenta plan benefits. The plans are aimed at premium users who want more connectivity on the go, but the Go5G Plus plan also gives subscribers access to the same device upgrade offers that are typically available only to new customers.

Read more: T-Mobile’s Unlimited Plans Explained

The CEO also put out a call for Congress to restore the Federal Communications Commission’s authority to put new wireless spectrum up for auction. That authority failed to get extended. and it expired on March 9. Though he didn’t suggest that T-Mobile was on the hunt for more spectrum, he said there was “never” enough spectrum available to the wireless industry to ensure American competitiveness. Earlier in April, T-Mobile President of Technology Neville Ray pleaded in a blog post for the FCC to grant T-Mobile the 2.5GHz licenses it won in Auction 108 back in March, which, he said, are “stuck in regulatory limbo.”

T-Mobile had 523,000 net customer additions for its high-speed home internet service, which uses fixed wireless access on its 5G network. When asked during the earnings call about the carrier’s trialing wired fiber internet in select areas, Sievert declined to share any updates aside from noting that T-Mobile is “very committed to being winners in broadband.” Instead, carrier executives championed its 5G home internet service as a way to get to customers who hadn’t already signed on to its mobile service. 

T-Mobile reported $15.5 billion in revenue over the quarter, up 3% from the same period last year. This broke down to $1.58 earned per share, which was above the $1.48 per share predicted by analysts polled by Yahoo Finance.

Shares of T-Mobile dropped 2.79% in after-hours trading.