AT&T Inc posted revenue that missed Wall Street estimates and its wireless subscriber growth was also slower than expected in its final quarter as the exclusive U.S. provider for the Apple Inc iPhone, sending shares down 3 percent.

AT&T added 400,000 net contract customers in the fourth quarter compared with the average expectation for almost 504,000 from eight analysts contacted by Reuters.

On Tuesday, its biggest rival Verizon Wireless reported 872,000 new contract customers. Verizon Wireless starts selling the iPhone in February, ending AT&T's more than three years of exclusive rights to the popular device.

AT&T, the No. 2 U.S. mobile operator on Thursday reported a profit of $1.09 billion, or 18 cents per share compared with a profit of $2.7 billion, or 46 cents per share in the same quarter the year before.

But excluding unusual items, AT&T earned 55 cents per share compared with the average analyst estimate for 54 cents a share according to Thomson Reuters I/B/E/S.

Operating revenue rose 2.1 percent to $31.36 billion from $30.71 billion in the year-ago quarter. On average analysts were expecting revenue of $31.47 billion, according to a poll from Thomson Reuters I/B/E/S.

AT&T said it expects consolidated revenue to grow this year but did not give a specific target.

It forecast earnings per share growth in the mid-single digit percentage range for the year as it expects both wireless and wireline profit margins to improve.

AT&T shares fell to $27.85 in early trade after closing at $28.73 in regular New York Stock Exchange trade.

Verizon Wireless is a venture of Verizon Communications and Vodafone Group Plc.

(Reporting by Sinead Carew; editing by Derek Caney, Dave Zimmerman)