Area Code 840

California

Area code 840 serves California, primarily San Bernardino, in the Pacific Time (PT) time zone. It is an overlay area code sharing territory with area code 909.

Published: Verified against NANPA and FCC records

Overlay Area Code

This area code shares its geographic footprint with an overlay code, so the same cities are served by two area codes. Because overlays leave existing numbers untouched, this region's relief planning favors adding codes over redrawing boundaries.

The codes serving this same region: area code 909 (San Bernardino).

In service since: 23-Feb-2021

Learn more about overlay and split area codes →

Demographics & Economics

Total Population
1,361,611
Population Density
2,220 people/sq mi
above U.S. average (U.S.: 95 people/sq mi)
Median Household Income
$90,112
above U.S. median (U.S.: $80,734)
Poverty Rate
13.7%
near U.S. average (U.S.: 12.5%)
Unemployment Rate
7.3%
above U.S. average (U.S.: 5.2%)
Education Attainment
Bachelor's Degree+
36.0%
near U.S. average (U.S.: 35.7%)
High School or Lower
31.9%

Statistics are population-weighted aggregations from Census ACS 5-year estimates. Population figures are approximate — see Sources & Methodology for details on how area code populations are derived.

See how this area code compares to all US area codes in the income ranking and density ranking.

Time Zone

  • Pacific Time (PT)

NANPA Relief Status

According to the latest NANPA analysis (July 2026), this area code is not currently listed as exhausting within the next 36 months. No relief planning is in progress for this NPA.

Source: NANPA NPA Relief Planning Reports · See all relief planning statuses

Current Time

Pacific Time (PT)
 
 

Prefix Utilization

Geographic Coverage

State

CA

Major Cities

  • San Bernardino
  • Fontana
  • Ontario
  • Rancho Cucamonga
  • Pomona
  • Rialto
  • Chino
  • Upland
  • Chino Hills
  • Redlands
  • Eastvale
  • Highland
  • Yucaipa
  • Colton
  • Diamond Bar
  • Rowland Heights
  • Montclair
  • Claremont
  • San Dimas
  • La Verne
  • Walnut
  • Loma Linda
  • Bloomington
  • Grand Terrace

and 13 more cities

Area Code 840 geographic coverage map (light mode)

Demographics

The estimated population served by area code 840 is approximately 1,361,611. The population density is 2,220 people per square mile, which is higher than the national average of 95. The median household income is $90,112, which is higher than the national median of $80,734. Approximately 36.0% of adults hold a bachelor's degree or higher, compared to the national rate of 35.7%. This rate is near the national average. The poverty rate stands at 13.7%, which is near the national rate of 12.5%.

History

Area code 840 serves as an overlay for the same territory as area code 909. It was introduced in 2021 to provide additional phone number capacity for the region. It shares its territory with area code area code 909.

County Coverage

Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 840).

CountyPopulationShare
San Bernardino, CA1,780,11373.1%
Los Angeles, CA422,82617.4%
Riverside, CA233,0279.6%

Area Code 840 Family Tree

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213310323714805818424562738619657909949661820626747760858840951442
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Total Codes
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Splits
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Overlays
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Max Depth

Area code 840 was originally assigned in 23-Feb-2021 to serve CA.

Call Context

Metropolitan area

This area code covers a metropolitan region in CA with moderate to high population density, centered on San Bernardino and surrounding communities.

Nearby Area Codes

Area codes geographically closest to 840.

Other Area Codes in California

Area codes that also serve California, linked for easy comparison.