AT&T sold 4.8 million iPhones in the first quarter.
The company sold 6 million smartphones in total.
The number almost certainly means that AT&T continues to be the largest retailer of iPhones in the U.S. Verizon Wireless sold 4 million units in the same period. Sprint Nextel reports its results tomorrow, but it's unlikely to top AT&T's number.
AT&T added 296,000 net contract customers in the first quarter.