The 670 area code covers Saipan, Tinian and 1 more place in the Northern Mariana Islands.
Area code 670 is in the Northern Mariana Islands, on Chamorro Time. It has been in service since July 1, 1997.
- Where
- Saipan, Tinian and Rota, the Northern Mariana Islands
- Time zone
- Chamorro Time
- In service since
- July 1, 1997
- Shares its area with
- No other area code
- Prefixes in use
- 35
- How to dial
- Local calls inside 670 can still be dialed with just 7 digits.
Find out who called you from a 670 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 (670) number is on today, use our free carrier lookup.
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Saipan holds 89% of the phone prefixes in area code 670.
A prefix is the three digits after the area code, and NANPA assigns each one to a town. Counting the 35 prefixes in use shows where 670 numbers are actually given out.
- Saipan31 prefixes, 89%
- Tinian2 prefixes, 6%
- Rota2 prefixes, 6%
Micronesian Telecommunications and PTI Pacifica hold the most phone number prefixes in area code 670, 15 prefixes each.
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 35 prefixes in use in 670 divide between carriers; holders this page does not name are grouped as other carriers.
| Carrier | Prefixes | Share |
|---|---|---|
| Micronesian Telecommunications | 15 | 43% |
| PTI Pacifica | 15 | 43% |
| Guam Wireless Telephone | 5 | 14% |
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.
670 has covered the same ground since 1997.
1997
670 goes into service on July 1, 1997.
A 670 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 670 are 671.
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 670.
Where is area code 670?
670 covers Saipan, Tinian and Rota in the Northern Mariana Islands.
What cities use area code 670?
The places holding the most 670 prefixes are Saipan, Tinian and Rota. The count comes from NANPA's prefix assignments as of October 1, 2026.
Which phone company owns area code 670?
No single phone company owns 670. NANPA's records show the largest holders of its 35 prefixes include Micronesian Telecommunications, PTI Pacifica and Guam Wireless Telephone. Numbers move between carriers, so check one exact number with a carrier lookup.
What time zone is area code 670 in?
670 is on Chamorro Time.
When did area code 670 start?
670 went into service on July 1, 1997.
How do I dial a 670 number?
Local calls inside 670 can still be dialed with just 7 digits.
Is 670 a toll-free number?
No. 670 is a regular area code for Saipan and Tinian in the Northern Mariana Islands, 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 670?
The closest are 671 (Hagåtña, Guam), measured between the centres of each area.
Who called me from a 670 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 670 a scam?
670 is a real the Northern Mariana Islands 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.