The stock, which is part of the Dow Jones industrial average, rose $1.57, or 3.2 percent, to $51.10 in morning trading. Just after the open, it hit a 12-year high of $51.55.
Verizon Wireless is the country's largest cellphone carrier, and keeps growing faster than its competitors, thanks in large part to its vast, fast and highly-rated network.
Analyst Christopher King at Stifel Nicolaus said the stock now appears fully valued, characterizing it as a situation of "perfection baked in ... but perfection should continue."
The New York-based phone company reported net income of $1.95 billion, or 68 cents per share, for the January to March period. That was up from $1.69 billion, or 59 cents per share, a year earlier.
Analysts polled by FactSet had on average expected earnings of 66 cents per share for the latest quarter.
First-quarter revenue rose 4 percent to $29.4 billion, just short of the average analyst estimate at $29.5 billion.
Service revenues at Verizon Wireless rose 8.6 percent to $16.7 billion, accounting for more than half of Verizon's overall revenue. At its closest rival AT&T Inc., wireless service revenue has been rising just over 4 percent per year.
The first quarter was a season of profit-taking for Verizon Wireless, after heavy spending in the fourth quarter to put the new iPhone 5 into 3 million hands. Like most other phone companies, Verizon subsidizes new smartphones by hundreds of dollars to bring the price down to $199 or less, then makes the money back in service fees over the run of a two-contract.
Verizon activated 7.2 million smartphones in the first quarter, down 2.6 million from the fourth quarter. That helped keep subsidies down and boosted operating income by 34 percent to $6.4 billion.
Verizon said 30 percent of its contract customers are already on the Share Everything plans it introduced last summer. The plans provide unlimited calling and texting and a "bucket" of data that can be shared across a family's Verizon devices.
Unfortunately for Verizon Communications, only 55 percent of Verizon Wireless' profits flow to its bottom line. The rest goes to joint-venture partner Vodafone Group PLC, the British cellphone carrier. Verizon Communications has a long-standing interest in buying out its partner, but so far, hasn't found a formula that it can afford and Vodafone will accept.
Verizon Wireless added a net 677,000 new devices under contract to its rolls in the quarter, meeting analyst expectations. That was up from 501,000 in the same quarter a year ago but down from the record-breaking 2.1 million in the fourth quarter.
Verizon said it activated 4 million iPhones in the quarter, half of which were the latest model, iPhone 5. Brian White at Topeka Capital Markets said the relatively strong iPhone sales are good news for Apple Inc., which reports its quarterly results on Tuesday, along with AT&T.
Apple's stock, however, was down 1.4 percent Thursday morning, hitting its lowest levels since 2011.
Verizon ended the quarter with 93.2 million devices under contract. That's nearly one for every U.S. household, and compares with 70.5 million with AT&T, as of the end of the year.