The amount of credit given depends on the device the company buys back and service plan a customer chooses. Those who sign up for both voice and data plans receive a higher credit.
Older BlackBerry devices run on the slower Mobitex wireless network. AT&T wants entice subscribers of that network to its next-generation 2.5G network, which provides voice and data services, international roaming, and the ability to send and receive messages and browse the Web.
"By providing customers with the flexibility of purchasing or leasing, coupled with a trade-in credit for their older devices, customers can now easily migrate from their less-robust, proprietary BlackBerry service to GSM/GPRS," Andre Dahan, president of AT&T Wireless Mobile Multimedia Services said in a statement.
The point of the program is clearly to drive adoption of AT&T Wireless' network, according to analyst Jason Tsai of equity research firm ThinkEquity Partners.
"AT&T Wireless is footing the bill for the conversion from Mobitex to GPRS," he said. "This is a positive for RIM because it will drive incremental revenue from hardware."
Tsai added that RIM receives better revenue per user from AT&T Wireless than Cingular, which maintains a Mobitex network, because of more favorable contract terms.
For AT&T, the deal also means better revenue opportunities on a per-subscriber basis. "By selling a BlackBerry with voice and data capabilities, a carrier is increasing their revenue by at least $35," Tsai estimated.
Devices can be leased for 24, 30 or 36 months for between $10 and $36.25 per month, depending on the terms of the contract.
AT&T Wireless had 21.1 million subscribers of its wireless services as of March 31. The trade-in program will end Sept. 30.