Warren, Ohio Area Code
Warren, OH utilizes an area code overlay in which area codes 234 and 330 serve the same geographic area. Ten digit dialing (area code + seven digit number) is necessary.
In addition to Warren, OH area code information read more about area codes 234 and 330 details and Ohio area codes.
Warren, OH is located in Trumbull County and observes the Eastern Time Zone. View our Times by Area Code tool.