Oct. 31, 2012 at 6:04 PM ET
AT&T and T-Mobile will let customers who live in Sandy's path use roaming on the other's carrier's network.
Both wireless carriers, who use the same GSM and UMTS standards, said Wednesday that the agreement will "enable roaming on their networks to customers of both companies in the heavily impacted areas and where capacity is available and for subscribers with a compatible device."
An AT&T spokesman told NBC News that almost all phones should be compatible. Capacity will be a different matter, as about 25 percent of cell towers were knocked by Sandy in affected states, and carriers are working to get service fully restored. New York and New Jersey have been very hard hit by crippled cell service.
A T-Mobile spokesman told NBC News said that the roaming arrangement, for both contract and prepaid customers, will be in effect as long as necessary.
"This will be seamless for T-Mobile and AT&T customers, with no change to their current rate plans or service agreements even if the phone indicates the device is attached to the other carrier’s network," the spokesman said.
T-Mobile also said "customers in New York City, Long Island, New Jersey, Connecticut and Pennsylvania, whether contract or prepaid customers, (will) continue to be able to use their service regardless of any inability to make payments on their accounts" until Nov. 8,.
One of the biggest issues now is finding power — and T-Mobile said as it re-opens its stores in the affected areas, all mobile users are "welcome to come in and charge their mobile phones."
Mobile users are being advised to check ahead of time to make sure the store is open and does have power. A store locator is here.
AT&T and T-Mobile both use the same type of wireless standards, GSM and UMTS, for their networks. Verizon Wireless and Sprint use a different standard, one known as CDMA.
In a statement, AT&T and T-Mobile said that customers of both networks "will be able to place calls just as they normally would, but their calls will be carried by whichever network is most operational in their area. This will be seamless for AT&T and T-Mobile customers with no change to their current rate plans or service agreements, even if the phone indicates the device is attached to the other carrier’s network."
In other words, if you are an AT&T customer, and you suddenly see "T-Mobile" at the top of your phone, don't fret about extra charges — just be glad you can make calls.
Both networks had a similar agreement for roaming after Hurricane Katrina in 2005, but "the scale of Sandy is unprecedented in terms of the geographic area it covers," said a spokesman.
AT&T, the nation's second largest carrier in terms of subscribers, had wanted to buy T-Mobile, but last year withdrew its $39 million bid after the Justice Department sued to block the merger, contending it would reduce competition and lead to higher prices.