840 area code — Pomona, CA geographic

Data: NANPA public reports, current as of July 28, 2026.

State
California
Major area
Pomona
Time zone
Pacific
In service since
2021-02-23
Split from
909
Overlay complex
840 / 909
Active prefixes
119
Rate centers
19
Carriers
14
Projected exhaust
1Q 2056

Area code 840 is a geographic code serving Pomona, California in the Pacific time zone. It has been in service since February 23, 2021. Together with 909 it forms the 840/909 overlay. Because of number portability and VoIP, the area code tells you where the number was issued, not where the caller is right now.

NANPA lists 119 active NXX prefixes in 840, assigned to 14 carriers. 119 of those prefixes are pooled — shared between carriers in thousands-number blocks. The code spans 19 rate centers (billing localities).

Its parent code is 909, which it left in 2021.

Official projections put exhaust for the 840/909 complex at 1Q 2056.

The dialing plan is 1+10D for home-NPA local calls and 1+10D across codes.

If a 840 call asks for money or personal data, treat the displayed number as unverified: hang up and reach the organization through its published number. Numbering data locates numbers, not callers.

Largest localities in 840

Largest rate centers in area code 840
Locality (rate center)Active prefixesAlso served by
Pomona 16 909
Arrowhead 14 909
Fontana 12 909
San Bernardino 11 909
Chino 8 909
Claremont 7 909
Ontario 7 909
Colton 6 909, 951
Upland 6 909
Redlands 5 909

FAQ

Where is a 840 number from?

840 is assigned to Pomona and surrounding areas of California in the Pacific time zone. The three digits after the area code (the prefix) narrow it down to a rate center.

Is 840 a toll-free number?

No. 840 is a geographic code; calls are billed like any other domestic call. Toll-free codes are 800, 833, 844, 855, 866, 877 and 888.

Why do 909 and 840 cover the same place?

They are overlays: when a code runs low on numbers, a new code is added over the same territory instead of splitting it. The 840/909 complex shares one service area, and local calls are dialed with 10 digits.

Will 840 run out of numbers?

NANPA's current forecast projects exhaust in 1Q 2056 — decades of capacity remain.

Why am I getting spam calls from 840 numbers?

Scammers spoof recognizable area codes so calls look local or familiar. A displayed 840 number does not prove the call originated there — see our guide to spotting spoofed calls.