Area Code Atlas

Establishment of area code 505 for New Mexico

In October 1947, area code 505 was established as part of the original North American Numbering Plan. It served the entire state of New Mexico as a single numbering plan area.

505 NPA Split, Creating 575 NPA (New Mexico)

505 NPA Split Suspended (New Mexico)

505 NPA; Petition for Approval of Relief Plan Dismissed - New Mexico

New Mexico Public Regulation Commission orders split of 505 NPA

On November 9, 2006, the New Mexico Public Regulation Commission ordered a two-way geographic split of the 505 area code. The northwestern region, including Albuquerque, would retain 505, while the rest of the state would transition to a new area code, 575.

New Mexico Public Regulation Commission orders split of 505 NPA

The New Mexico Public Regulation Commission ordered a two-way geographic split of the 505 area code on November 9, 2006. The northwestern region, including Albuquerque, would retain 505, while the remainder of the state would transition to the new 575 area code.

NPA 505 Split, Creating NPA 575 (New Mexico)

Permissive dialing period begins for 575 and 505

Permissive dialing for the new 575 area code began on October 7, 2007, allowing calls to be completed using either the old or new area code for affected numbers. This period provided time for customers to adjust to the new dialing procedures following the split of 505.

NPA 575 created from split of 505

Area code 575 was created on October 7, 2007, from a split of the original 505 area code. The new code was assigned to eastern and southern New Mexico, while 505 was retained for the northwestern and central regions.

505 area code split to create 575

Area code 505 was split on October 7, 2007, with the northern and central regions of New Mexico, including Albuquerque and Santa Fe, retaining 505, while the rest of the state was assigned area code 575.

Reminder to update networks with the new 575 NPA for the 505 NPA Split in New Mexico

Mandatory dialing of 575 and 505 begins after split

Mandatory dialing of the correct area code for affected numbers began on October 5, 2008. After this date, calls dialed with the incorrect area code were routed to an intercept recording, marking the end of the permissive dialing period for the 505/575 split.

Mandatory ten-digit dialing for area code 505 due to 988 implementation

Mandatory ten-digit dialing was implemented for area code 505 on October 24, 2021, as part of the nationwide transition to support 988 as the three-digit code for the National Suicide Prevention Lifeline.

Transition to 10-digit dialing for 505 due to 988 implementation

The 505 area code transitioned to ten-digit dialing by October 24, 2021, following the nationwide designation of 988 as a dialing code for the National Suicide Prevention Lifeline, which conflicted with existing 7-digit dialing in the area.