The 679 area code serves Detroit, Michigan, and its surrounding Wayne County suburbs. It launched on November 7, 2025, as an overlay for the historic 313 area code, meaning both codes now cover the same geographic area. Because of this overlay, all local calls in the region require 10-digit dialing (area code + phone number).
What Is the 679 Area Code?
Area code 679 is a North American Numbering Plan (NANP) areas codes assigned to southeastern Michigan. It doesn’t replace 313; it sits on top of it. Both 313 and 679 numbers now serve the same footprint: Detroit and most of its closest suburbs in Wayne County, including Hamtramck, Highland Park, Dearborn, Dearborn Heights, Allen Park, Ecorse, the Grosse Pointe communities, Harper Woods, Inkster, Melvindale, Lincoln Park, Redford, River Rouge, and Taylor.
Where Is the Area Code Located?
The 679 area code covers Detroit and Wayne County, Michigan, in the Eastern Time Zone (ET, GMT-5). It spans roughly 15 cities within a single county, with Detroit as the anchor city.
Major cities covered
Major cities and areas served by the 679 area code include:
When Did the Area Code Start?
The 679 area code officially went into service on November 7, 2025. It was the 479th area code activated in the NANP system and the 13th area code assigned to the state of Michigan. The idea for 679 actually dates back further than its launch date. It was first reserved in February 2000 as a relief plan for 313, but that overlay was suspended just two months later after pushback.

Why Was the Area Code Created?
The 679 area code exists because 313 was running out of available phone numbers. Detroit’s growing population of mobile devices, VoIP lines, and business phone systems steadily consumed the finite pool of numbers available under 313 alone. Rather than splitting the region into two geographically separate area codes (which would force some residents to change their numbers), the Michigan Public Service Commission chose to overlay a second area code on the identical service area.
Do I Need to Change My Phone Number?
No. If you currently have a 313 number, you keep it exactly as is. The 679 area code only applies to newly issued phone numbers in the region going forward. Existing customers are not required to switch, port, or update their numbers in any way
Does the Area Code Require 10-Digit Dialing?
Yes. Because 679 is an overlay of 313, both codes now share the same numbering area, and the North American Numbering Plan requires mandatory 10-digit dialing (area code + 7-digit number) for all local calls in an overlay region, even when calling a next-door neighbor.
Area Code: Quick Facts
| Detail | Information |
|---|---|
| Region served | Detroit and Wayne County, Michigan |
| Time zone | Eastern Time (ET), GMT-5 |
| In-service date | November 7, 2025 |
| Overlay of | Area code 313 |
| State ranking | 13th area code in Michigan |
| National ranking | 479th area code in the NANP |
| Dialing requirement | Mandatory 10-digit dialing |
| Number of cities served | Approximately 15 |
| County | Wayne County |
Is a Number the Same as a Detroit Number?
Yes. A 679 number is a legitimate local Detroit-area phone number. It serves the same geographic area as a 313 number and offers the same call rates and service quality. The only difference is the area code itself. Telephone providers began issuing 679 numbers after they used all available 313 numbers. Businesses can use a 679 number to establish a local presence in Metro Detroit, just as they use a 313 number.
Frequently Asked Questions (FAQs)
Conclusion
The 679 area code isn’t a replacement for Detroit’s iconic 313; it’s a companion. Launched on November 7, 2025, as an overlay covering the same Wayne County footprint, 679 exists purely to keep new phone numbers available as the region’s population, businesses, and devices continue to grow.
