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zipcodes.pro — AREA-CODE/340

340 area code

Area code 340 is in the U.S. Virgin Islands. Most of its numbers are issued in the rate centre NANPA calls CHTAMSTTHS. Local time there is , Atlantic Time. In service since 1997, with no overlay.

Time zone
Atlantic
Overlays
none
In service since
1997
Rate centres
4
Prefixes assigned
58 (580,000 numbers)

Who calls from a 340 number

NANPA records the carrier each block of 340 numbers is assigned to. Of the 580,000 340 numbers assigned, 59% are with mobile carriers (Liberty Mobile USVI, T-Mobile and Vitelcom Cellular); 29% with local phone companies (Innovative Telephone); 12% with cable, internet-calling, business and other carriers (Lumen Technolgies St. Croix).

That is who the numbers were assigned to: people keep their number when they change carrier, so any one number may have moved since.

Carriers holding the most 340 numbers
CarrierKindShare
Innovative TelephoneLandline29%
Liberty Mobile USVIMobile28%
T-MobileMobile14%
Vitelcom CellularMobile14%
Lumen Technolgies St. CroixCable, VoIP, other7%
AT&T MobilityMobile2%

An area code says where a number was issued, not where the caller is: people keep their numbers when they move, and caller ID can be set to show any number, which the FCC calls spoofing. If a call you did not expect asks for money or personal details, the FCC advises hanging up and calling the company back on a number you look up yourself. Unwanted calls can be reported to the FTC at ReportFraud.ftc.gov.

Where 340 numbers are issued

NANPA's rate centres with the most 340 prefixes (each prefix is 10,000 numbers), under NANPA's own abbreviated names.

Rate centres using area code 340
Rate centrePlacePrefixes
CHTAMSTTHS — 42
CHNSTDSTCR — 7
ST CROIX — 7
FRKSTDSTCR — 2

Which code covers where you are now? What area code am I in? answers from your location.

Questions about area code 340

Where is area code 340?

Area code 340 is in the U.S. Virgin Islands. Most of its numbers are issued in the rate centre NANPA calls CHTAMSTTHS.

What time zone is area code 340 in?

Atlantic time.

Is a 340 number a mobile or a landline?

It can be either. 59% of 340 numbers are assigned to mobile carriers and 29% to local phone companies (NANPA, 2026-10-10); the rest are with cable, internet-calling, business and paging carriers. A number keeps its area code when it moves to another carrier.

Does a 340 number mean the caller is in the U.S. Virgin Islands?

Not necessarily. An area code says where the number was first issued. People keep their numbers when they move or switch carriers, and calling software can show any number, so a 340 call can come from anywhere.

Source: NANPA NPA database, central office code and thousands-block assignments, 2026-10-10. Places are matched to NANPA's rate centres by name; see sources.

Cite this page

zipcodes.pro. “Area code 340.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/area-code/340

Underlying data is public domain or openly licensed — sources, vintages and licences.