AT&T said it will shut down its TDMA network in 18 markets this summer and take the remainder of the network down by early next year. The carrier aims to port all TDMA customers to its more spectrally efficient GSM network. The eighteen markets include a block from New Mexico to Texas to Kentucky, and will be offline by July 15. While AT&T did not disclose the number of subscribers still using TDMA, it did say the network facilitates a mere 1 percent of its calling traffic.

For more on AT&T's TDMA plans:
- read this article from RCR News