The 313 area code covers Detroit in Michigan.
Area code 313 is in Michigan, on Eastern Time. In the 313 area, phone numbers are given out in Wayne County. It has been in service since 1947. 679 covers the same area, so two neighbours can have different area codes.
- Where
- Wayne County, Michigan
- Time zone
- Eastern Time
- In service since
- 1947
- Shares its area with
- 679 (since 2025)
- Prefixes in use
- 769
- How to dial
- Local calls need all 10 digits: 313-555-0142.
Find out who called you from a 313 number.
Enter the full 10-digit number to see who it is listed to and the city and state on the listing. It is the same free check as our who called me lookup. To see only the caller ID name on the number, use our free CNAM lookup. To see whether it is a mobile, a landline or a VoIP line, use our free VoIP checker. To see which carrier a (313) number is on today, use our free carrier lookup.
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Detroit holds every phone prefix in area code 313.
A prefix is the three digits after the area code, and NANPA assigns each one to a town. Counting the 769 prefixes in use shows where 313 numbers are actually given out.
- Detroit769 prefixes, 100%
Michigan Bell (AT&T) holds the most phone number prefixes in area code 313: 244 of 769.
NANPA, which runs the North American numbering plan, assigns each prefix (the three digits after the area code) to one carrier. Here is how the 769 prefixes in use in 313 divide between carriers; holders this page does not name are grouped as other carriers.
| Carrier | Prefixes | Share |
|---|---|---|
| Michigan Bell (AT&T)AT&T's landline company | 244 | 32% |
| T-MobileMobile network | 141 | 18% |
| AT&T MobilityMobile network | 95 | 12% |
| BandwidthSupplies numbers to VoIP and app-based phone services | 28 | 4% |
| American MessagingPaging network | 24 | 3% |
| Level 3 (Lumen)Lumen's business and wholesale network | 22 | 3% |
| 28 other carriers | 215 | 28% |
63% of these prefixes are pooled, which means the blocks of 1,000 numbers inside them can belong to other carriers. Any number can also have been moved to another carrier since, so this shows who holds the prefixes, not who serves a given number.
Want the carrier of one exact number? Our free carrier lookup checks it, because numbers move between carriers.
Source: NANPA central office code assignments, October 1, 2026.
313 has been split 2 times and overlaid 2 times since 1947.
1947
313 starts as an overlay on 313: new numbers on the same ground.
1947
313 is added on top of 313, so new numbers here can get either code.
1993
On December 1, 1993, 810 splits off and takes part of the 313 area.
1997
On December 13, 1997, 734 splits off and takes part of the 313 area.
2025
On November 7, 2025, 679 is added on top of 313, so new numbers here can get either code.
A 313 number on your screen can still be a scam, because caller ID is easy to fake.
- Let an unknown call go to voicemail. A real caller leaves a message; a robocaller usually does not.
- Look the number up with the box above before you call back, because calling back tells a robocaller your line is live.
- Hang up on anyone who wants gift cards, crypto or a wire transfer, or asks you to read out a code that was just texted to you.
- Report unwanted robocalls at reportfraud.ftc.gov, or paste a suspicious message into our free scam checker.
The area codes closest to 313 are 248, 586 and 810.
This list measures the distance between the centres of each area, across state lines, and shows codes that share one area together.
These are the questions people ask most about area code 313.
Where is area code 313?
313 covers Detroit in Michigan. In the 313 area, phone numbers are given out in Wayne County.
What state is area code 313 in?
Michigan. 313 is a Michigan area code on Eastern Time.
Which phone company owns area code 313?
No single phone company owns 313. NANPA's records show Michigan Bell (AT&T) holds the most 313 prefixes, 244 of 769, followed by T-Mobile and AT&T Mobility. Numbers move between carriers, so check one exact number with a carrier lookup.
What time zone is area code 313 in?
313 is on Eastern Time.
When did area code 313 start?
313 went into service in 1947, as an overlay on 313: new numbers for the same area.
Is 313 the same area as 679?
Yes. 679 (since 2025) covers the same ground as 313. Nobody's number changed when it was added; new lines simply get whichever code has numbers left, so two neighbours can have different codes.
How do I dial a 313 number?
Local calls need all 10 digits: 313-555-0142.
Is 313 a toll-free number?
No. 313 is a regular area code for Detroit in Michigan, not a toll-free one. The toll-free codes in North America are 800, 833, 844, 855, 866, 877 and 888.
What area codes are near 313?
The closest are 248/947 (Pontiac, Michigan), 586 (Mount Clemens, Michigan), 810 (Flint, Michigan) and 517 (Lansing, Michigan), measured between the centres of each area.
Who called me from a 313 number?
Enter the full 10-digit number in the lookup above. It returns the listed owner where there is a public record, where the number is registered, and whether it is a mobile, a landline or a VoIP line.
Is area code 313 a scam?
313 is a real Michigan area code, so the code itself is not a warning sign. Scam callers fake local-looking numbers on purpose, so judge the call by what the caller asks for, and look the number up before calling back.
Put this lookup on your site: our free area code widget takes two lines of code and shows any US area code's state, time zone and local time.
Source: NANPA, the North American Numbering Plan Administrator: its area code database and prefix assignments, as of October 1, 2026.