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US area code · California

840 area code

Where the 840 area code is, its overlay and how to dial a +1 840 number from anywhere.

CoversCaliforniaTime zonePacific (PT)TypeOverlay
Quick answer

The 840 area code is in California, United States (Pacific (PT)). To call from abroad: +1 840 555-0123. It is an overlay, so all 10 digits are dialled.

StateCalifornia
Time zonePacific (PT)
TypeOverlay
10-digit dialingRequired
In service since13-Jun-2019

The 840 area code is a geographic North American Numbering Plan (NANP) code covering California. It has been in service since 13-Jun-2019 and sits in the Pacific (PT) time zone.

Overlay 840 shares its region

Several area codes cover the same geographic area, so two neighbours can have different codes. Because of the overlay, you must dial all 10 digits (area code + number) even for local calls.

840909

How to dial a 840 number

From abroad+1 840 555-0123
Within the US / Canada1 840 555-0123
Locally (same area)840 555-0123

Other California area codes

209213279310323341350357369408415424442510530559

Frequently asked questions

Where is the 840 area code?

The 840 area code is in California, United States (Pacific (PT)).

Is 840 an overlay area code?

Yes. 840 overlays the same region as 909, so callers dial all 10 digits.

Do I have to dial 10 digits for 840?

Yes — dial the area code plus the seven-digit number.

How do I call a 840 number from another country?

Dial your exit code (or +), then 1, then 840, then the number: +1 840 555-0123.

Source: NANPA numbering plan. An area code covers a region, not a precise address — a 840 number does not pinpoint a street or ZIP code.

Number holders in area code 840

Each prefix (the three digits after the area code) is assigned by NANPA to one telephone company. 140 prefixes are in use in 840, shared by 16 companies. The largest holders:

CompanyPrefixesShare
T-Mobile USA, Inc.3223%
Fractel, LLC2619%
Onvoy, LLC2216%
New Cingular Wireless PCS, LLC1712%
Cellco Partnership Dba Verizon Wireless129%
Multiple Ocn Listing96%

Source: NANPA central office code assignments. A number keeps its original prefix when it is ported to another carrier.

Complaints about 840 numbers

Reports to the FTC, last 30 days
210
Recorded messages or robocalls
78%
Rank among area codes
#330 of 670
Most reported subjects
Reducing your debt (credit cards, mortgage, student loans) (108)
Other (66)
Calls pretending to be government, businesses, or family and friends (24)

Period Aug 26 – Sep 24, 2026. These are the numbers shown on the caller ID of the reported calls; many are spoofed and do not belong to the real caller.

Source: US Federal Trade Commission, Do Not Call reported calls data (daily files).

All US area codes United States +1 Map of area code 840 — cities & rate centres

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