Qwest Corporation is a Bell Operating Company owned by CenturyLink. It was formerly named U S WEST Communications, Inc. from 1991 to 2000, and also formerly named The Mountain States Telephone and Telegraph Company from 1911 to 1991. It includes the former operations of Malheur Bell, Northwestern Bell and Pacific Northwest Bell as well.

It is one of two of the original 22 Bell Operating Companies (the other being Frontier West Virginia) not to be owned by a Baby Bell formed in 1984.