Area Code 251

Alabama

Area code 251 serves Alabama, primarily Mobile, in the Central Time (CT) time zone. It was created from a split of area code 334.

Published: Updated:

Split Area Code

This area code was created by splitting an existing area code into separate geographic regions. When a split occurs, some customers in the original area code region are assigned the new area code.

This area code was split from area code 334 (Montgomery).

In service since: 18-Jun-2001

Learn more about overlay and split area codes →

Demographics & Economics

Total Population
864,231
Population Density
63 people/sq mi
below U.S. average (U.S.: 93 people/sq mi)
Median Household Income
$58,119
below U.S. median (U.S.: $75,144)
Poverty Rate
16.1%
above U.S. average (U.S.: 11.5%)
Unemployment Rate
5.6%
above U.S. average (U.S.: 3.6%)
Education Attainment
Bachelor's Degree+
24.7%
below U.S. average (U.S.: 33.7%)
High School or Lower
37.0%

Statistics are population-weighted aggregations from Census ACS 5-year estimates. Population figures are approximate — see Sources & Methodology for details on how area code populations are derived.

See how this area code compares to all US area codes in the income ranking and density ranking.

Time Zone

  • Central Time (CT)

NANPA Relief Status

According to the latest NANPA analysis (July 2026), this area code is not currently listed as exhausting within the next 36 months. No relief planning is in progress for this NPA.

Source: NANPA NPA Relief Planning Reports · See all relief planning statuses

Current Time

Central Time (CT)
 
 

Prefix Utilization

Geographic Coverage

State

AL

Major Cities

  • Mobile
  • Daphne
  • Fairhope
  • Foley
  • Prichard
  • Tillmans Corner
  • Saraland
  • Gulf Shores
  • Spanish Fort
  • Atmore
  • Orange Beach
  • Bay Minette
  • Robertsdale
  • Satsuma
  • Chickasaw
  • Monroeville
  • Semmes
  • Brewton
  • Theodore
  • Jackson
  • Loxley
  • Citronelle
  • Grand Bay
  • Evergreen

and 59 more cities

Area Code 251 geographic coverage map (light mode)

Historical Timeline of Area Code 251

Area code 251 was activated on June 18, 2001, as the 300th area code in the North American Numbering Plan. Created via a geographic split from area code 334, it relieved prefix exhaustion in southwestern Alabama where only 155 of 800 central office codes remained by April 2000. Source: Wikipedia

Key milestones:

  • 1947: Alabama assigned its original area code 205 as part of the initial North American Numbering Plan
  • 1995: Area code 334 created via split from 205, covering southern Alabama including Mobile
  • 2000: By April, only 155 of 800 prefixes remained in 334. The Alabama PSC unanimously approved the 334/251 split on October 3 (Verizon Communications)
  • 2001: NANPA issued PL-254 on January 2. Area code 251 activated June 18 with a six-month permissive dialing period (NANPA)
  • 2002: Mandatory 251 dialing began January 7. Existing 334 numbers in the region were grandfathered
  • 2021: Mandatory 10-digit dialing took effect October 24, required by FCC Order FCC 20-100 to support the 988 Suicide & Crisis Lifeline (Alabama PSC)

Area code 251 was the last area code in Alabama to transition from 7-digit to 10-digit local dialing. It serves the Mobile metropolitan area and surrounding counties in southwestern Alabama.

Regulatory History

FCC Order FCC 20-100 (2020) required area code 251 to transition to mandatory 10-digit dialing by October 2021 because the 988 central office code was already assigned in the 251 area, conflicting with the new 988 Suicide & Crisis Lifeline. The code's regulatory history also includes the Alabama PSC's original 2000 approval of the 334/251 geographic split. Source: Alabama PSC

YearEventDocketRegulatory Action & Impact
2000334/251 Split ApprovalAlabama PSCAlabama PSC unanimously approved (3-0) the geographic split of 334 to create 251 covering southwestern Alabama, after finding only 155 of 800 central office prefixes remained (Verizon Communications)
2001NANPA Planning LetterPL-254NANPA formally notified the industry of the 334/251 split with a June 18, 2001 implementation date and six-month permissive dialing period (NANPA)
2020FCC 988 Lifeline OrderFCC 20-100FCC approved 988 as the 3-digit abbreviated dialing code for the National Suicide Prevention Lifeline. Area code 251 was required to transition to mandatory 10-digit dialing because 988 was already assigned as a central office code in the 251 area (Alabama PSC Fact Sheet)
2021Mandatory 10-Digit DialingAlabama PSCAlabama PSC announced mandatory 10-digit dialing for area code 251 beginning October 24, 2021, with permissive dialing from April 24, 2021. Area code 334 was not affected because 988 was unassigned there (Alabama PSC Press Release)

County Coverage

Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 251).

CountyPopulationShare
Mobile, AL413,82947.9%
Baldwin, AL255,93629.6%
Conecuh, AL53,8276.2%
Escambia, AL47,3865.5%
Monroe, AL45,5645.3%
Washington, AL24,1272.8%
Clarke, AL14,7261.7%
Choctaw, AL8,0000.9%
Wilcox, AL8360.1%

Area Code 251 Family Tree

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Splits
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Overlays
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Max Depth

Area code 251 was originally assigned in 18-Jun-2001 to serve AL.

Call Context

Mixed urban-rural area

This area code spans a mix of urban centers and rural communities across AL, with Mobile as a primary city.

Nearby Area Codes

Area codes geographically closest to 251.

Other Area Codes in Alabama

Area codes that also serve Alabama, linked for easy comparison.