Detroit Area Code Changes: ‘679’ Starting Soon

Starting soon, the Detroit area is getting a new area code! Right now, the region is covered by the 313 area code, but it will soon share space with a new one—area code 679. Don’t worry—if you already have a 313 phone number, you won’t lose it. However, new customers may receive either a 313 or 679 area code when they sign up for a new number. The changes won’t affect rates or local calling areas, but there is one important update: dialing patterns.

Starting on April 7, 2025, you'll need to dial 10 digits (area code + phone number) for local calls. This begins during the "Permissive Dialing Period," which lasts for 6 months. During this time, calls made with just 7 digits will still go through, but it’s a good idea to start dialing 10 digits right away so you’re ready for the change. Long-distance calls will continue to require 11 digits (1 + area code + phone number).

This is also the time to check that any automatic dialing systems you use are updated. Things like life safety alarms, medical devices, fax machines, speed dialers, and even your contact list might need to be updated with the new 10-digit dialing format. Don’t forget to check your advertising materials, personal ID tags, and websites as well!

By October 7, 2025, the change will be mandatory. If you don’t dial 10 digits, you might hear a recording reminding you to include the area code. If you have any questions about these changes or the new dialing pattern, you can reach out to your phone service provider or visit this website for more details.

Detroit’s 313 area code has become a symbol of the city’s strength and spirit. It’s now part of the city’s identity, appearing on T-shirts and even tattoos. But the state is running out of 313 phone numbers and plans to add a new area code, 679, for Detroit and some nearby suburbs.

"The 313 area code is expected to run out by the third quarter of 2025, meaning most of its phone numbers are already taken, and only a few will be left available, aside from those that are returned and reassigned," said the Michigan Public Service Commission in a 2023 news release.