The 712 area code covers Sioux City, Council Bluffs and 228 more places in Iowa.
Area code 712 is in Iowa, on Central Time. In the 712 area, phone numbers are given out most in Woodbury County, then Pottawattamie and Sioux counties. It has been in service since 1947.
- Where
- 8 counties in Iowa, mostly Woodbury County, Pottawattamie County and Sioux County
- Time zone
- Central Time
- In service since
- 1947, one of the original area codes
- Shares its area with
- No other area code
- Prefixes in use
- 633
- How to dial
- Local calls inside 712 can still be dialed with just 7 digits.
Find out who called you from a 712 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 (712) number is on today, use our free carrier lookup.
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Sioux City holds 12% of the phone prefixes in area code 712.
A prefix is the three digits after the area code, and NANPA assigns each one to a town. Counting the 633 prefixes in use shows where 712 numbers are actually given out.
- Sioux City73 prefixes, 12%
- Council Bluffs29 prefixes, 5%
- Sergeant Bluff13 prefixes, 2%
- Spencer11 prefixes, 2%
- Le Mars10 prefixes, 2%
- Carroll9 prefixes, 1%
- Storm Lake8 prefixes, 1%
- Harlan8 prefixes, 1%
Also served: Atlantic, Denison, Red Oak and Onawa and 218 smaller places.
Windstream holds the most phone number prefixes in area code 712: 83 of 633.
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 633 prefixes in use in 712 divide between carriers; holders this page does not name are grouped as other carriers.
| Carrier | Prefixes | Share |
|---|---|---|
| WindstreamLandline company | 83 | 13% |
| Qwest (Lumen)Lumen's landline company | 64 | 10% |
| AT&T MobilityMobile network | 43 | 7% |
| FrontierLandline company | 26 | 4% |
| T-MobileMobile network | 22 | 3% |
| UScellularMobile network | 20 | 3% |
| 92 other carriers | 375 | 59% |
69% 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.
712 has covered the same ground since 1947.
1947
712 is one of the original North American area codes.
A 712 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 712 are 515, 641 and 507.
This list measures the distance between the centres of each area, across state lines, and shows codes that share one area together.
Iowa has 4 other area codes.
These are the questions people ask most about area code 712.
Where is area code 712?
712 covers Sioux City, Council Bluffs, Sergeant Bluff and Spencer and 226 more places in Iowa. In the 712 area, phone numbers are given out most in Woodbury County, then Pottawattamie and Sioux counties.
What state is area code 712 in?
Iowa. 712 is an Iowa area code on Central Time.
What cities use area code 712?
The places holding the most 712 prefixes are Sioux City, Council Bluffs, Sergeant Bluff, Spencer, Le Mars, Carroll, Storm Lake and Harlan, out of 230 places in all. The count comes from NANPA's prefix assignments as of October 1, 2026.
Which phone company owns area code 712?
No single phone company owns 712. NANPA's records show Windstream holds the most 712 prefixes, 83 of 633, followed by Qwest (Lumen) and AT&T Mobility. Numbers move between carriers, so check one exact number with a carrier lookup.
What time zone is area code 712 in?
712 is on Central Time.
When did area code 712 start?
712 is one of the original North American area codes, in service since 1947.
How do I dial a 712 number?
Local calls inside 712 can still be dialed with just 7 digits.
Is 712 a toll-free number?
No. 712 is a regular area code for Sioux City and Council Bluffs in Iowa, 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 712?
The closest are 515 (Des Moines, Iowa), 641 (Mason City, Iowa), 507/924 (Rochester, Minnesota) and 402/531 (Omaha, Nebraska), measured between the centres of each area.
Who called me from a 712 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 712 a scam?
712 is a real Iowa 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.