JEFFERSON CITY —Some residents in Missouri are going to have to change the way they make calls in the near future after the Missouri Public Service Commission and the North American Numbering Plan Administrator (NANPA) announced the creation of a new area code.

The new code (235) will exist in the current (573) area code in Missouri. As part of that process, residents should prepare for 10-digit local dialing.

The 235 area code will be added as an overlay to the 573 region. An overlay is the addition of another area code (235) to the same geographic region served by an existing area code (573). The good news is that an overlay doesn't require customers to change their existing area code, however, it does require customers to dial the area code to complete local calls.

“Customers are reminded that the 573 area code is not going away and if they have a telephone number with the 573 area code, they will not lose or have to change their telephone number,” said Public Service Commission Chairman Scott Rupp in a press release. “An overlay is a more efficient and less disruptive way to alleviate the exhaustion of available telephone numbers which is occurring in the 573 area code.”

The Timeline

August 26, 2023:

A six-month permissive dialing period begins. This will allow residents adequate time to adjust to the dialing changes. During this period, local calls can be made with either 7 or 10 digits, and all calls that are local will continue to be local even though you dial 10 digits.

February 24, 2024:

All local calls made within the 573 area code must be placed using 10 digits (area code + the 7-digit telephone number). On and after that date, calls placed using just 7 digits will not be completed.

March 24, 2024:

New telephone lines or services may be assigned numbers using the new 235 area code.

What You Need To Know

  • Your current telephone number, including your current area code, will not change
  • What is a local call now will remain a local call
  • If you seek new phone service on and after March 24, 2024, you may be assigned a phone number with the 235 area code
  • You will need to dial the area code + telephone number for all local calls, including calls within the same area code
  • You will continue to dial 1 + area code + telephone number for all long-distance calls
  • The price of a call, coverage area, or other rates and services will not change due to the overlay
  • You can still dial just three digits to reach 911 and 988. You can also dial three digits to reach 211, 311, 511, and 811 where available.
  • Remember to identify your telephone number as a 10-digit number and include the area code when giving the number to friends, family, business associates and customers.

The 573 area code serves communities such as, but not limited to:

  • Jefferson City
  • Columbia
  • Rolla
  • Cape Girardeau
  • Poplar Bluff
  • Sikeston
  • Mexico
  • Hannibal
  • Camdenton
  • Waynesville
  • Farmington
  • Caruthersville

In addition to the permissive dialing period, customers should ensure all services, automatic dialing equipment, applications, software, or other types of equipment are reprogrammed to dial 10 digits if they are programmed to dial just 7 digits and recognize the new 235 area code as a valid area code. Examples include

  • Life-safety systems
  • Fax machines
  • Internet dial-up numbers
  • Gates
  • Ankle monitors
  • Speed dialers
  • Mobile phone contact lists
  • Call forwarding settings, 
  • Voicemail services 

Be sure to check your business stationery, advertising materials, personal checks, and your personal or pet ID tags to ensure the area code is included in your telephone number.

Important safety and security equipment, such as medical alert devices, and alarm and security systems must be programmed to use 10-digit dialing. Many systems operate on 10-digit dialing by default, but some older equipment may still use 7 digits. Please contact your medical alert or security provider if you are not sure whether your equipment needs to be reprogrammed to accommodate the upcoming change to 10-digit local dialing. Any needed reprogramming of alarm and home security equipment must be done between August 26, 2023, and February 24, 2024.

For additional information, please visit the Missouri Public Service Commission or contact your local telephone service provider.