All carriers sell plans that offer thousands of peak and weekend minutes for preset monthly prices, but usually any unused minutes disappear at the end of every month.
Cingular changed that in August when it introduced new local calling plans that let customers add unused peak minutes to the next month's total. Local calling plans charge extra for long distance and for roaming onto another carrier's network.
On Tuesday, Cingular extended rollovers to national calling plans that cost $40 or more a month. National plan members get the same number of minutes, but aren't charged extra for roaming or long distance. People now signing up for national calling plans can roll over unused peak minutes, a Cingular representative said.
But Cingular won't let its customers stockpile minutes indefinitely. For both national and local calling plans, rollovers end after 12 months.
Cingular's rollover plans are another sign of the ongoing price war among the nation's five major U.S. wireless carriers, which spent the past two years one-upping one another with cheaper phone plans.
Cheaper calling plans attracted tens of millions of new customers, but also cut into the carriers' revenues. Many of the nation's wireless providers are now financially ailing, and two major U.S. carriers expected to merge by year's end.
Cingular's move pressures competitors such as Verizon Wireless and AT&T Wireless to offer similar rollover plans, said wireless analyst Alan Reiter, president of an industry consulting company called Wireless Internet & Mobile Computing. But so far, none has introduced its own version.
The Cingular national plans with rollover-anytime minutes are available nationwide, except in Tulsa, Okla.; Houston and Austin, Texas; in parts of New York; Kauai, Hawaii; and Puerto Rico. A Cingular representative said Tuesday that those areas would get the new plans by mid-November.