(Adds details from report)
By Julia Love
MEXICO CITY, Oct 16 (Reuters) - America Movil, Latin America's largest telecommunications firm by number of subscribers, saw its net profit surge in the third quarter as it reaped foreign exchange gains and shifted customers to more lucrative plans.
The company, which is controlled by the family of Mexican billionaire Carlos Slim, reported a net profit of 18.96 billion pesos ($1 billion) for the third quarter, rebounding from a loss in the same period last year when its results were battered by a Colombian arbitration panel ruling.
But the net profit fell short of analysts' expectations of 22.6 billion pesos, according to a poll conducted by Reuters.
America Movil logged revenue of 248.07 billion pesos during the quarter.
America Movil's results have been hampered by currency swings in recent quarters, but foreign exchange rates played to the company's favor this time. America Movil said in a report to investors that its results benefited from currency improvements in Mexico and Colombia following elections in those countries.
Another driver of the company's success was its campaign to shift its business from prepaid to more lucrative postpaid plans, in which users sign contracts. America Movil said it netted 1.1 million new postpaid subscribers during the quarter, up 7.6 percent from last year, expanding the base across its key markets.
The company is also profiting as users consume more data. Data traffic soared 78.2 percent, spiking in Brazil, the United States and Mexico.
America Movil's EBITDA, a closely watched measure of profitability, reached 71.8 billion pesos, up 7.7 percent.
In Mexico, America Movil's home market which it has long dominated, EBITDA rose 15.2 percent, a jump the company attributed to cost-cutting.
In Brazil, the company said its results benefited from a legal victory in a tax dispute.
$1 = 18.7175 pesos at end-September Reporting by Julia Love; additional reporting by Noe Torres and Sheky Espejo Editing by Christine Murray and Sandra Maler