Area Code Atlas

Area code 713 established as one of the original Texas area codes

In 1947, area code 713 was established as one of the original area codes in Texas, covering the southeast region including Houston.

NPA 409 split from 713

On March 19, 1983, area code 713 was divided for the first time. Area code 409 was created to serve the northern, eastern, and western portions of the original 713 territory, while 713 was reduced to the immediate Houston area.

NANP - INTRODUCTION OF INTERCHANGEABLE CENTRAL OFFICE CODES IN THE TEXAS 713 NPA

NANP-OVERLAY OF 713 (TEXAS) NUMBERING PLAN AREA (NPA)

NANP-Split of 713 (Texas) Numbering Plan Area (NPA)

Area code 281 split from 713

Area code 281 was created on November 2, 1996, as a geographic split from 713 to serve most of Houston's suburbs outside Beltway 8, while 713 was retained for Houston inside the beltway and existing cellphone customers. The split was intended as a long-term solution to number exhaustion.

Declaration of Jeopardy Situation in NPA 713 (Texas)

Extraordinary NPA-Specific Jeopardy Conservation Procedures Announced for 281 and 713 Numbering Plan Areas in Houston, Texas

Elimination of 713/281 (Houston, TX) Split Line and Introduction of Overlay NPA 832

713/281 boundary erased and 832 overlay introduced

The boundary between area codes 713 and 281 was eliminated on January 16, 1999, creating a single overlay region for Houston. Area code 832 was simultaneously introduced as an additional overlay, and ten-digit dialing became mandatory for all calls in the region.

Area code 832 overlays 713 and 281; boundary erased

Area code 832 was introduced on January 16, 1999, as an overlay to the 713/281 region in the Houston area, erasing the boundary between 713 and 281. This change formed an overlay complex and required mandatory ten-digit dialing for all calls in the region.

Ten-digit dialing becomes mandatory in Houston area

Ten-digit dialing became mandatory for all calls in the Houston area on January 16, 1999, coinciding with the introduction of area code 832 and the elimination of the boundary between 713 and 281.

Public Utility Commission of Texas announces addition of area code 346 overlay for Houston

The Public Utility Commission of Texas announced on May 9, 2013, that area code 346 would be added as a fourth overlay to the existing 713, 281, and 832 area codes to address the exhaustion of available numbers in the Houston region.

NPA 346 to Overlay NPAs 281/713/832 (Texas)

Area code 346 overlay introduced in Houston area

Area code 346 was added on July 1, 2014, as the fourth overlay area code for the Houston metropolitan area to provide additional numbering resources, joining 713, 281, and 832 in serving the same geographic region and allowing new phone numbers in the area to be assigned the new code.

Public Utility Commission of Texas approves 621 overlay for Houston

On October 12, 2023, the Public Utility Commission of Texas approved the addition of area code 621 as an all-services distributed overlay for the 281, 346, 713, and 832 area codes in the Houston area, to address projected numbering resource exhaustion. The new code will serve the same geographic area as 281, 346, 713, and 832.

NPA 621 overlay on 281/346/713/832 announced

NPA 621 to Overlay NPA 281/346/713/832 (Texas)

Area code 621 activated as overlay for Houston area

Area code 621, approved in 2023, was activated on January 23, 2025, as the fifth overlay area code for the Houston metropolitan area, joining 713, 281, 832, and 346 to prevent exhaustion of numbering resources.