Area code 603

Area code 603 is the sole area code for the U.S. state of New Hampshire in the North American Numbering Plan (NANP). It was created as one of the original 86 numbering plan areas in October 1947.

In 2011, area code 603 was said to be nearing exhaustion and a second area code for New Hampshire was expected to be activated by 2013 as a statewide overlay plan.^[1] As a result of changes in allocation policies and a reclamation of a large block of previously allocated telephone numbers, including number pooling, the exhaustion time frame has been moved to at least 2032.^[2]