Cell phone providers have begun sending out messages to customers in the 480, 602 and 623 area codes about dialing changes that will take effect on Aug. 12.

In 2021, the Arizona Corporation Commission approved the boundary change among the three area codes, allowing each code to serve the entire Phoenix geographic area.

“This change is to ensure consumers and businesses in the Phoenix area will have continued access to telephone numbers from their wireline/wireless/voice over internet protocol service providers of their choice,” ACC stated in a release at the time.

On Sept. 12, any of the three area codes may be assigned to those who request a new telephone number or an additional telephone line.

ACC officials said medical alert devices and alarm/security systems must be programmed to the 10 digits, noting that many systems operate on 10-digit dialing by default. Some older equipment may need updating.

“Be sure to check your website, personal and business stationary, advertising materials, personal and business checks, contact information, your personal or pet ID tags, and other such items to ensure the area code is included,” ACC officials said.

There will be no changes to:

*Telephone numbers or area codes.

*The price of a call, coverage area or other rates and services.

*What is a local call now will remain a local call regardless of the number of digits dialed.

*Continue to dial 1+ the area code + telephone number for all long-distance calls.

*Dial just three digits to reach 711 (relay services) and 911 (emergency services).

*If 211, 311, 411, 511, 611, or 811 are currently available in a community, dial the codes with just three digits.

For more information, visit the AZCC website at azcc.gov/utilities/telephone/all-about-area-codes.