251 Area Code: Mobile, Alabama

Anchored on Mobile, Alabama, the 251 area code covers the Gulf Coast corner of the state. Mobile is one of the older European-settled cities in the Deep South, founded by the French and passed between several colonial powers before it became American, and the layered influence is still visible in the street grid of the historic core, the Carnival traditions that long predate New Orleans's, and the working port at the mouth of Mobile Bay. The 251 footprint reaches inland from the bay through farm country and timber land.

A handful of cities outside the 251 region — Birmingham, Huntsville, and Montgomery among them — turn up frequently in records linked to numbers that carry this code. Their appearance reflects how phone numbers travel with their owners across porting events, prior registrations, and address linkages rather than anything about geography. Our records cover 339 distinct prefixes within 251, which represents the directory's documented subset; the actual count of prefixes in active use is larger.

Mobile's demographic profile leans modest by national measures. Typical home values run well below the US median, and household incomes follow suit. The city's median age sits a touch under the national reading, and the population is comparable to other mid-sized Southern coastal cities — large enough to support a substantial port economy and university footprint, smaller than the inland Alabama hubs that dominate the state's population statistics.