AT&T fared poorly across the board, earning the worst-possible score in all categories related to value, service and customer support, except for the "texting" service category. More than half of survey respondents who used AT&T owned some version of the iPhone.
"Our survey suggests that an iPhone from Verizon Wireless, which is rumored, could indeed be good news for iPhone fans," said Paul Reynolds, electronics editor for Consumer Reports.
The carrier with the highest score was U.S. Cellular, which serves in 26 states mostly in the South and Midwest. To see the full results in the January issue, subscribe to Consumer Reports.
In second place was Verizon Wireless, which is widely rumored to receive the iPhone in early 2011. Verizon also recently began selling Apple's iPad, bundled with a MiFi 2200 Intelligent Hotspot.
Nipping at Verizon's heels is Sprint, which scored better than Verizon in terms of e-mail customer support. Verizon was previously the top U.S. provider since 2003.
In fourth, but still ahead of AT&T, was T-Mobile, which respondents said has poor service, but the best telephone customer support in the industry.
Consumer Reports carrier rankings, from the January issue.
In response to the Consumer Reports survey, AT&T sent out the following response:
"We take this seriously and we continually look for new ways to improve the customer experience. The fact is wireless customers have choices and a record number of them chose AT&T in the third quarter, significantly more than our competitors."
The company also cited a survey from last month, which found that AT&T has wireless speeds much faster than Verizon. That same study, from Global Wireless Solutions Inc., also found that AT&T's dropped call rate is within one-tenth of a percent of Verizon.