King of Prussia, PA utilizes an area code overlay in which area codes 484 and 610 serve the same geographic area. The area code overlay was put into service on June 5, 1999 at which time area code 484 was implemented as an overlay of area code 610. Area Code 610 was created from a split of area code 215 in 1994. Ten digit dialing (area code + seven digit number) is necessary because two different homes in the same geographic area can have the same seven digit phone number but each would have a different area code.
In addition to King of Prussia, PA area codes 484 and 610 serve southeastern Pennsylvania including the larger cities and communities of Allentown, Bethlehem, Chester, Drexel Hill, Easton, Norristown, Pottstown, Radnor Township, and Reading in addition to many smaller communities within the 484 and 610 service area.
King of Prussia, PA is located in Montgomery County and observes the Eastern Time Zone. View our Times by Area Code tool.