What happened

Shares of wireless carrier company T-Mobile (TMUS 0.92%) jumped on Wednesday, rising as much as 4.7%. As of noon ET, however, the stock was up about 3.5%.

The telecom stock's gain came following T-Mobile's second-quarter earnings report this morning. Though the quarterly update featured a top and bottom line that both missed analysts' consensus forecasts, subscriber additions were strong. In addition, the company raised its full-year outlook for subscriber growth.

So what

T-Mobile added 1.7 million postpaid net customers during Q2, the company said in its earnings release Wednesday morning. Not only was this the company's best second-quarter postpaid subscriber growth ever but the net additions were more than AT&T and Verizon's Q2 additions combined, management explained.

"Our relentless focus on putting customers first delivered yet another outstanding quarter for T-Mobile with industry-leading postpaid and broadband customer growth," said CEO Mike Sievert in the company's earnings release.

Now what

The quarter's strong momentum enabled management to raise its full-year guidance. The outlook boost, management said, is "further proof that our commitment to addressing customer pain points in this challenging macro-economic environment is working."

Management said it now expects to add between 6 million and 6.3 million postpaid net customers during 2022. This is up from a previous forecast for 5.3 million to 5.8 million full-year subscriber additions. The company also said it now expects free cash flow, when including payments for merger-related costs, to be between $7.3 billion and $7.6 billion for the full year. While the top end of this guidance range is unchanged, the lower end increased from $7.2 billion previously.