Those T-Mobile partners have plenty of 4G LTE service in major cities that offer fast data services, Legere said. Even though T-Mobile has expanded LTE coverage in the U.S., critics often ding the carrier for having weak or spotty coverage outside of major U.S. cities. Analysts said it remains to be seen how thorough the coverage is in Canada and Mexico.
Even with such concerns, analysts said the new plan will appeal to travelers, both consumers and business.
"T-Mobile is stealing the industry's -- and especially AT&T's thunder -- by expanding the free calling area to Mexico and Canada," said Roger Entner, an analyst at Recon Analytics. "The new plan is most appealing to people who, no surprise, call and travel to Mexico and Canada the most."
For business customers using Mobile without Borders, T-Mobile adapted its "Un-carrier for Business" plans announced in March.
Under the March announcement, the first 20 business lines would cost $16 a line (or $15 a line for 21 lines or more) per month, which includes voice and text and 1 GB of data. With the Mobile without Borders plan, the first 10 business lines cost nothing extra, but there is a $1 added cost per phone line for 11 or more lines, T-Mobile officials said.
With the Mobile without Borders plan, 50 percent of the calls, texts and data used every three months must be done from inside the U.S. That restriction keeps the plan devoted to U.S.-based customers, T-Mobile said.
The March business plan was immediately so successful that it produced a 120 percent increase in traffic flow into 3,000 T-Mobile stores, Legere said. T-Mobile might provide more details on the bottom-line impact of its business plans when it announces earnings on July 30, he hinted.
"Overall, we've been astounded" by the interest from businesses, said Rakesh Mahajan, senior director of marketing for @Work at T-Mobile. Some customers have said they didn't realize T-Mobile was in the market for business customers.
Mahajan said Mobile without Borders could be expanded beyond Mexico and Canada to other countries. "We started with the biggest opportunity and customers will figure out where we go next," he said. Legere and other officials didn't commit to offering such a plan in Europe, when asked.
Mexico in particular has been an attractive market because trade barriers have been lowered in recent years, meaning more U.S. businesses are working with manufacturing partners in Mexico, he said.
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