Thread: Will 900/1800/1900 mhz work with At&t cingular?

Will 900/1800/1900 mhz work with At&t cingular? if not with which company in the U.S? (T-mobile)?

If you look on your phone (or whatever that is) it'll have a company name on it.
ie: Cingular, Verizon, MetroPCS, etc., etc.

If you see that company name, then it only works with that company.

For example my phone says verizon on it, so that means my phone only works with the verizon company.