Area Code Atlas

NPA 503 split to create 541

Area code 503 was split in November 1995, with most of Oregon outside the northwest corner receiving the new area code 541, to address number exhaustion and geographic division, limiting 503 to northwestern Oregon including Portland.

Extraordinary NPA-Specific Jeopardy Conservation Procedures Announced for the 541 NPA (Oregon)

NPA 458 overlay on 541 announced

NPA 458 to Overlay NPA 541 (Oregon)

Permissive 10-digit dialing begins in 541/458 overlay area

Permissive 10-digit dialing began in July 2009 in the 541/458 overlay area to prepare customers for mandatory 10-digit dialing due to the overlay implementation.

Mandatory 10-digit dialing in 541/458 overlay area

In January 2010, ten-digit dialing became mandatory for all calls in the 541 and 458 area codes. This change was required due to the implementation of the 458 overlay.

NPA 458 overlays 541

On February 10, 2010, area code 458 was added as an overlay to the 541 region in Oregon. The overlay was implemented to address the exhaustion of available numbers in the 541 area.