North American Numbers Source-cited · ownership disclosed
Area code
840
In service
United States · since 2021

Inland Empire (overlay)

Area code 840 is an all-services overlay on area code 909, serving the Inland Empire since February 23, 2021. It shares the exact geography of 909.

The essentials Numbering data · NumberResearch · as of 2026-09-18
Place
Inland Empire (overlay)
Type
geographic
Status
in service
In service since
2021
Projected exhaust
2056 Q1

Status, dates and counts are read from NumberResearch (NANPA / CNAC / FCC records). Assignment records show initial assignees, not the carrier serving a number today.

A · Where it is

Where 840 is

Same territory as area code 909: far-eastern Los Angeles County, southwestern San Bernardino County, and small parts of Riverside County, California..

Communities served wholly or partly by 840:

San BernardinoOntarioRancho CucamongaFontanaPomonaChino

Overlay shares the 909 footprint; representative list.

B · Relationships

How it relates to other codes

The codes 840 was split from, spawned, or shares its area with. A split divides the map and changes some numbers; an overlay shares the same ground and changes none — what's the difference?

Overlay · 2021 909 Inland Empire (San Bernardino) All-services overlay on 909, effective February 23, 2021 (permissive dialing July 2020 to January 2021).
What's changing. All-services overlay on 909; new subscribers receive 840 numbers, ten-digit dialing required (re-check against NANPA).
C · History

How 840 got here

2021-02-23
Area code 840 added as an all-services overlay on 909 (re-check against NANPA).
Source: Wikipedia
D · Capacity

How full it is

Prefixes assigned
140
Prefixes available
660
Thousands-blocks assigned
1,194

Prefix-assignment counts describe allocation to carriers, not how many individual numbers are in use. Full technical records: NumberResearch ↗.

Compare 840 with another code →
Sources
Wikipedia ↗
Area codes 909 and 840
NumberResearch.org ↗
Live status, dates, assignment counts and exhaust forecast — data as of 2026-09-18 (CC BY 4.0).

Place, relationships and history above are compiled by North American Numbers from the sources listed and last checked 2026-09-18. A check date is not an expert review — see how this is made. Flag an error.