North American area code 602 is a state of Arizona telephone area code that covers most of the city of Phoenix.It was one of the original area codes established in October 1947 and had originally covered the entire state of Arizona until 1995, when area code 520 was created as the state's second area code.he area code divider between 602 and 623 was drawn in such a way that in some neighborhoods, homes only a few hundred feet away from each other may have different area codes.