Area code 520

By the late 1980s, the state needed a second area code to satisfy population growth and increased demand for telephone numbers.

Mountain Bell, the incumbent local exchange carrier in the state, requested a second area code for Arizona in 1988.

[2] This meant that in-state toll and collect calls would require dialing the area code.

The new area code became mandatory in Flagstaff, Prescott, and Yuma on June 30, 1996, and in Tucson on December 31, 1996.

The telecommunications industry favored a split similar to that eventually adopted but moving Cochise County into the new area code.

Area code 435 Area code 970 Area code 505 Area code 575 Area code 775 Area codes 702 and 725 Area codes 760 and 442 Telephone numbers in Mexico Area code 520 Area code 928 Area codes 602, 480, and 623
Clickable map of Arizona area codes in blue (and border states) with area code 520 shown in red