Numbering

See also:

• Business: Telecommunications: Regulation  (97)
• Reference: Directories: Address and Phone Numbers: Area Codes  (25)

Area Code Information - Detailed information on the history and current developments in North American NPA allocations..

International Numbering Plans - A collection of all international numbering plans in the world. Some features require a paid subscription..

800 Service Management System - Information about the central database for US toll free number management..

The Telephone Exchange Name Project - The historical relationship between North American telephone exchange names and numbers..

Help build the largest human-edited directory on the web. Submit a Site - Open Directory Project - Become an Editor