Wireless carrier Virgin Mobile USA Inc , which has agreed to be acquired by Sprint Nextel Corp , reported a higher quarterly profit that beat market estimates as it continued to benefit from the growth of its profitable hybrid customer base.

Hybrid gross additions grew to 63 percent of total gross additions in the second quarter, from 55 percent in the first quarter, resulting in a 20 percent year-over-year growth in total hybrid gross customer additions in the first half of 2009, the company said.

Hybrid plans, which have some benefits of both prepaid and postpaid options, offer customers fixed number of minutes at a standard price without a contract.

Virgin Mobile said it was confident of its 2009 outlook for adjusted EBITDA and free cash flow.

On July 28, Virgin Mobile and Sprint Nextel said they signed a deal that valued Virgin Mobile at about $483 million.

The company said second-quarter net income attributable to common stockholders rose to $16.8 million, or 23 cents per share, from $3.5 million, or 7 cents per share, a year earlier.

Operating revenue fell 3.8 percent to $307.6 million.

Analysts on average had expected earnings of 18 cents per share, excluding exceptional items, on revenue of $332.2 million, according to Reuters Estimates.

Virgin Mobile shares closed at $4.86 Friday on the New York Stock Exchange.

(Reporting by S. John Tilak in Bangalore; Editing by Gopakumar Warrier)