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The 423 area code covers Chattanooga, Johnson City, Kingsport, and Bristol across two disconnected pockets of East Tennessee. Here's the history, coverage map, and how to get a local number.
Curious who just called from an unfamiliar prefix? This 425 area code guide covers its exact cities, full numbering history, and whether answering is safe now.
The 430 area code overlays 903 in northeast Texas, a corner where four states nearly meet. See what it covers, why ten digits are needed, and how dialing works.
The 432 area code covers the Permian Basin around Midland and Odessa. See the West Texas cities it reaches, why ten digits are required, and how oil shapes it.
Curious about the 434 area code? See exactly which Central Virginia cities it covers, why it was created, and how to claim a matching business number today.
Find out where the 440 area code reaches in Ohio, why it was added as a real split from 216, and how to confirm a 440 call is genuinely legitimate.
The 458 area code overlays area code 541 across most of Oregon, from the Pacific coast to the Idaho border. See coverage, history, dialing rules, and a surprising Mountain Time pocket.
Area code 463 is a pure overlay covering Indianapolis and its suburbs, sharing every city with area code 317. Learn its history, coverage, and how to spot a spoofed IRS scam call.
See which Connecticut cities the 475 area code covers, why ten-digit dialing is mandatory, and how the overlay affects Bridgeport and New Haven phone numbers.
Find every city the 478 area code covers, learn the 2000 dialing history, spot scam calls fast, and see how businesses stay reachable across central Georgia now.
The 484 area code overlays 610 across the Lehigh Valley and Philadelphia's suburbs, sharing the exact same footprint rather than splitting it. Here's the history, coverage, and how to claim a number.
The 503 area code once covered all of Oregon for 48 years before shrinking to 10 counties around Portland. See coverage, the 971 overlay history, and dialing rules.
The 505 area code covers Albuquerque, Santa Fe, and northern New Mexico, but a close 2006 regulatory vote nearly split it apart. See the cities it covers, its history, and how to spot scam calls.
The 508 area code covers Worcester, Cape Cod, and both Martha's Vineyard and Nantucket, making it the only Massachusetts code that reaches the islands. Learn its history, coverage, and how to spot a scam call.
The 509 area code covers Spokane, Yakima, the Tri-Cities, and Walla Walla across eastern Washington. Learn its 1957 origin, coverage area, dialing rules, and how to get a local number.
Find out where the 513 area code reaches in Ohio, why it dates back to the original 1947 numbering plan, and how to confirm a 513 call is genuinely legitimate.
The 518 area code covers Albany and New York's Capital District, and it's one of the only original 1947 codes in the state that never split. See its history, coverage, and how to spot scam calls.
The 531 area code overlays 402 across eastern Nebraska, home to Omaha and Lincoln. See what it covers, why ten digits are required, and what a 531 call signals.
The 539 area code overlays northeastern Oklahoma's 918 region and was the state's first-ever overlay. See coverage, history, dialing rules, and how to spot spoofed Tulsa calls.
Wondering about the 540 area code? See which Shenandoah Valley and Roanoke cities it covers, its numbering history, and how to claim a matching number today.
The 541 area code covers most of Oregon outside Portland, from Eugene and Bend to Medford, without ever centering on one dominant city. See coverage, history, and dialing rules.
Getting calls from the 551 area code? Discover every New Jersey city and county it covers, why it overlays area code 201, and how to spot scam calls today fast.
The 564 area code shares identical territory with 360 across western Washington, added in 2017 to relieve numbering pressure. Discover the cities it reaches and how to claim a local number now.
Discover everything about the 567 area code covering Toledo and northwest Ohio, including its 2002 launch as Ohio's first overlay, and how to spot scam calls.