A common nickname given to the U.S. regional telephone companies that were formed from the breakup of AT&T ("Ma Bell") in 1984. Baby Bells were created in accordance with antitrust legislation, which is designed to create more competition within the industry.

Upon the initial breakup of AT&T, the Baby Bells included Nynex in New York and New England; Bell Atlantic, BellSouth and Ameritech in the Midwest; and Southwestern Bell, U.S. West and Pacific Telesis in California and Nevada. Over time, however, these companies have gone through several more corporate changes, such as acquisitions and mergers. As a result, the industry has been consolidated into a few domestic telephone providers.