The area code 484 is located in Allentown, Pennsylvania.
Area code 484 serves Allentown, Pennsylvania, and the wider Lehigh Valley in eastern Pennsylvania. It overlays area code 610 and was introduced in 1999 to meet growing demand for phone numbers, so 10-digit dialing is required for local calls. The 484/610 region sits north and west of Philadelphia and follows Eastern Time, covering key communities, colleges, and business hubs across southeastern Pennsylvania.
"Allentown is Pennsylvania’s third-largest city." — U.S. Census Bureau
Major cities and landmarks covered by the 484/610 overlay include:
In practical terms, new phone numbers in the region may receive a 484 area code, while older lines may still use 610; both work the same across the shared footprint. The area includes major highways like I-78 and the Pennsylvania Turnpike, busy logistics centers, and popular destinations such as the King of Prussia Mall and Lehigh Valley International Airport (ABE). Thanks to the overlay, callers should always dial the area code, even for local numbers, which helps keep enough numbers available without changing existing phone lines.