Area code 671 – Guam
671 has served Guam since 1997. It is still largely empty: 95 of 786 number blocks allocated. Other CLEC / VoIP holds 100.0% of those blocks, which is unusually concentrated for a US area code. All of its numbers sit in a single telephone rate center covering the whole area.
- State
- Guam
- In service since
- 1997
- Time zone
- Chamorro
- Shares area with
- No overlay
Who holds 671 number blocks
Share of the 95 assigned NXX blocks (12.1% of the 786 possible), across 8 carriers. This is share of number blocks, not of subscribers.
- Other CLEC / VoIP100%
Rate centers in 671
NANPA allocates number blocks to rate centers and records their names abbreviated to ten characters, so these are NANPA's codes rather than place names – CHAMPAURBN is Champaign-Urbana, NWYRCYZN01 is a New York City zone. We show them unchanged instead of guessing at the full names. This code has a single rate center covering its whole area.
Timeline
- 1997 671 goes into service in Guam.
More about 671
Separate pages for the questions that need their own answer: what time it is there, what the complaint data says, who holds the number blocks, and how the code compares with the one it shares its area with.
Frequently asked about 671
What state is area code 671?
Guam.
Which carrier owns 671 numbers?
Other CLEC / VoIP holds the largest share of assigned number blocks at 100.0%. This is share of number blocks, not of subscribers – people keep their numbers when they switch carriers.
Do I need to dial 10 digits in 671?
Yes – ten digits for local calls in 671, because it shares its area with another code.
Sources and verification
- NANPA – NPA Database (npa_report.csv), file date 11/01/2026, retrieved Nov 1, 2026
- NANPA – CO Code Assignment Records, All States (utilized), file updated 11/01/2026, retrieved Nov 1, 2026
NANPA dialing note for this code: “10D”. Reviewed by the data desk. Spotted an error? Request a correction.