AT&T said Friday it is ahead of schedule for 4G LTE network deployments and has now reached 103 U.S. cities.
Previously, AT&T had predicted it would reach 100 cities by the end of 2012.
All the major U.S. carriers are in a race to build widespread LTE networks offering greater speeds to help smartphone and tablet data users take advantage of wireless video streaming, gaming and other functions.
AT&T's coverage now includes areas affecting more than 150 million people, twice the number at the end of 2011, the company said.
The carrier plans to expand LTE to 250 million people by the end of 2013 and to 300 million by the end of 2014.
AT&T also reminded customers that its widespread 4G HSPA+ network is faster than 3G networks of both Verizon Wireless and Sprint. When a customer cannot get LTE coverage over AT&T, the wireless signal usually reverts to an HSPA+ signal.
Wireless speeds vary according to how many people are using a single cell tower and other factors, although carriers generally advertise LTE speeds as up to 10 times faster than 3G speeds, with HSPA+ often at three times 3G speeds.
In an area where LTE has recently been introduced by a carrier and there are few LTE customers, downlink speeds can soar to more than 20 Mbps. In some cities recently added to AT&T's LTE network, downlink speeds have reached 50 Mbps, based on emailed reports by Computerworld readers. Analysts note that it is unrealistic to use early network rollouts as an indication of LTE speeds in coming years.
Generally, carriers with LTE often average 8 Mbps to 12 Mbps on downlinks and 3 Mbps to 5 Mbps on uplinks.
Verizon got a head start on LTE and advertises that it has reached more than 440 cities, making it the largest LTE provider globally.
On Tuesday, Sprint said it had begun LTE work in nine more cities, including Minneapolis/St. Paul, after previously announcing more than 125 cities where LTE is coming. So far, Sprint's service reaches 32 cities. While Sprint is behind AT&T and Verizon in providing LTE service, it advertises unlimited data plans that the other carriers do not.
Fourth-largest carrier T-Mobile USA is planning to kick off LTE expansion in 2013, but already offers fast 4G HSPA+ service.
Matt Hamblen covers mobile and wireless, smartphones and other handhelds, and wireless networking for Computerworld. Follow Matt on Twitter at @matthamblen or subscribe to Matt's RSS feed. His email address is firstname.lastname@example.org.