840

San Bernardino, California

California · Pacific (UTC-8) · — · 18 cities

State
California
Major City
San Bernardino
Time Zone
Pacific (UTC-8)
Current Local Time
—
Cities Served
18

Cities Served by Area Code 840 (18 cities)

Chino+1 codeChino Hills+1 codeClaremont+1 codeColton+1 codeDiamond Bar+1 codeFontana+1 codeHighland+1 codeLoma Linda+1 codeMontclair+1 codeOntario+1 codePomona+1 codeRancho Cucamonga+1 codeRedlands+1 codeRialto+1 codeSan Bernardino+1 codeUpland+1 codeWalnut+1 codeYucaipa+1 code
Additional Details
Established
2021
Type
Overlay
Active Prefixes
133
Wireless Lines
46%

About Area Code 840

Area code 840 was introduced in 2021 as an overlay code, sharing the same geographic region as an existing area code to meet growing demand for phone numbers in the San Bernardino area. The area is in the Pacific time zone. It covers 18 cities and communities including Chino, Chino Hills, Claremont, Colton, Diamond Bar and 13 more.

Phone Number Prefixes in Area Code 840

133 active NXX prefixes — 46% wireless, 54% landline. Each prefix (NXX) represents up to 10,000 phone numbers.

T-Mobile 32 (24%)Fractel 26 (20%)Onvoy 17 (13%)AT&T Mobility 15 (11%)Verizon Wireless 12 (9%)
PrefixCarrierTypeRate Center
840-200FractelLandlineChino
840-201AT&T MobilityWirelessFontana
840-202AT&T MobilityWirelessPomona
840-203AT&T MobilityWirelessS Berndino
840-204AT&T MobilityWirelessS Berndino
840-205Bandwidth.comLandlineClaremont
840-206AT&T MobilityWirelessChino
840-207T-MobileWirelessArrowhead
840-208Bandwidth.comLandlineClaremont
840-209T-MobileWirelessArrowhead
840-210T-MobileWirelessFontana
840-211Multiple Ocn ListingLandline
840-212T-MobileWirelessChino
840-213T-MobileWirelessRedlands
840-214T-MobileWirelessMarshall
840-215T-MobileWirelessHighland
840-216T-MobileWirelessArrowhead
840-217T-MobileWirelessFontana
840-218Verizon WirelessWirelessChino
840-219T-MobileWirelessCalimesa
840-220Bandwidth.comLandlineRialto
840-221Hd CarrierLandlineS Berndino
840-222FractelLandlineS Berndino
840-223Bandwidth.comLandlineCalimesa
840-224AT&T MobilityWirelessS Berndino
840-225AT&T MobilityWirelessPomona
840-226OnvoyLandlinePomona
840-227Verizon WirelessWirelessS Berndino
840-228Verizon WirelessWirelessColton
840-229Verizon WirelessWirelessClaremont
840-230Boost SubscribercoWirelessPomona
840-231T-MobileWirelessPomona
840-232T-MobileWirelessFontana
840-233T-MobileWirelessArrowhead
840-234FractelLandlineArrowhead
840-235CommioLandlineColton
840-236OnvoyLandlineClaremont
840-237OnvoyLandlineOntario
840-238AT&T MobilityWirelessPomona
840-239OnvoyLandlineFontana
840-240OnvoyLandlineDiamondbar
840-241OnvoyLandlineRialto
840-242OnvoyLandlineUpland
840-243T-MobileWirelessPomona
840-244T-MobileWirelessDiamondbar
840-245T-MobileWirelessRedlands
840-246T-MobileWirelessEtiwanda
840-247T-MobileWirelessHighland
840-248T-MobileWirelessFontana
840-249T-MobileWirelessMarshall
840-250T-MobileWirelessArrowhead
840-251T-MobileWirelessRedlands
840-252T-MobileWirelessMentone
840-253T-MobileWirelessCalimesa
840-254OnvoyLandlineRialto
840-255OnvoyLandlineS Berndino
840-256T-MobileWirelessUpland
840-257T-MobileWirelessColton
840-258Verizon WirelessWirelessHighland
840-259AT&T MobilityWirelessPomona
840-260T-MobileWirelessPomona
840-261AT&T MobilityWirelessFontana
840-262T-MobileWirelessArrowhead
840-263AT&T MobilityWirelessFontana
840-264AT&T MobilityWirelessPomona
840-265T-MobileWirelessArrowhead
840-266Verizon WirelessWirelessS Berndino
840-267AT&T MobilityWirelessPomona
840-268AT&T MobilityWirelessMarshall
840-269SpectrumLandlineOntario
840-270AT&T MobilityWirelessOntario
840-271Verizon WirelessWirelessFontana
840-272SpectrumLandlineChino
840-273OnvoyLandlineMentone
840-274OnvoyLandlineArrowhead
840-275Verizon WirelessWirelessPomona
840-276Verizon WirelessWirelessUpland
840-277Verizon WirelessWirelessClaremont
840-278T-MobileWirelessArrowhead
840-279Verizon WirelessWirelessOntario
840-280Teleport Communications AmericaLandlineS Berndino
840-281T-MobileWirelessColton
840-282OnvoyLandlineChino
840-283OnvoyLandlineArrowhead
840-284OnvoyLandlineChino
840-285OnvoyLandlineFontana
840-286T-MobileWirelessArrowhead
840-287OnvoyLandlineMarshall
840-288MCI/VerizonWirelessS Berndino
840-300FractelLandlineRedlands
840-311Multiple Ocn ListingLandline
840-333FractelLandlinePomona
840-336FractelLandlineColton
840-345FractelLandlinePomona
840-356FractelLandlineArrowhead
840-400FractelLandlineOntario
840-411Multiple Ocn ListingLandline
840-444FractelLandlineArrowhead
840-465FractelLandlineChino
840-466Ton80 CommunicationsLandlineUpland
840-500FractelLandlineBigbear Cy
840-511Multiple Ocn ListingLandline
840-555Multiple Ocn ListingLandlineDir Asst
840-587FractelLandlineS Berndino
840-588FractelLandlineDiamondbar
840-600FractelLandlineColton
840-611Multiple Ocn ListingLandline
840-666FractelLandlineFontana
840-677FractelLandlineEtiwanda
840-688FractelLandlineCrestline
840-699FractelLandlineOntario
840-700Landline
840-711Multiple Ocn ListingLandline
840-777Terra Nova TelecomLandlinePomona
840-788FractelLandlineFontana
840-799FractelLandlineRialto
840-800FractelLandlineUpland
840-804OnvoyLandlineClaremont
840-811Multiple Ocn ListingLandline
840-837Ton80 CommunicationsLandlinePomona
840-840SpectrumLandlineOntario
840-877FractelLandlineMarshall
840-888Terra Nova TelecomLandlineRedlands
840-899FractelLandlineHighland
840-900FractelLandlineRialto
840-911Multiple Ocn ListingLandline
840-950Landline
840-958Landline
840-959Landline
840-976Landline
840-977FractelLandlineClaremont
840-998Verizon WirelessWirelessHighland
840-999Terra Nova TelecomLandlineUpland

All 40 area codes in California

840209213310323341350357369408415424442510530559562619626628650657661669707714738747760805818820831837858909916925949951

About Area Code 840

Area code 840 hit the scene in 2021, right when California's Inland Empire was buzzing with new residents and businesses. Picture this: San Bernardino, with its sunny streets and growing communities, needed more phone numbers to keep up with all the calls from folks chatting about daily life or sealing deals. So, 840 stepped in as an overlay, sharing the stage with existing codes to handle the demand without splitting things up. That means if you're in Chino or Fontana, you might now see 840 popping up on your caller ID, right alongside the familiar ones. These areas stretch from the urban vibe of Colton to the quieter corners of Highland and Loma Linda, painting a picture of suburban sprawl mixed with city energy. Back then, the reason for its creation was straightforward—population growth in places like Diamond Bar and Claremont meant phones were ringing off the hook, and we just needed more lines. It's one of those modern additions that keeps everything connected in this part of SoCal, where mountain views meet everyday hustle. Folks here deal with everything from commuting to LA to enjoying local parks, and 840 makes sure no one misses a beat. Whether you're a long-timer or just moved in, this code is all about keeping the conversations flowing in a region that's always on the move.

⚠ Scam & Spam Alert for 840

In areas like San Bernardino covered by 840, scam calls can show up just like anywhere else in California. You might get hit with IRS scams, where someone pretends to be from the government demanding payment for taxes you don't owe. Then there's the auto warranty racket, with callers pushing you to renew a policy that never existed. Medicare fraud is another one, especially targeting older residents in places like Chino Hills, offering fake services or asking for personal details. These calls often come out of the blue, trying to trick you into handing over money or info. Don't fall for the pressure; most of these are just attempts to catch you off guard. Here's a simple tip: If something sounds fishy, hang up and call back the official number yourself to check if it's legit. That way, you're not giving scammers an easy win.

Local Snapshot

San Bernardino's population is around 220,000, but the whole county tips over 2 million, making it a pretty crowded spot in Southern California. Logistics and warehousing drive the economy here, with big trucks rolling through thanks to major highways that connect to LA and beyond. The area is famous for its outdoor spots, like the nearby San Bernardino Mountains, where people hit the trails for hiking or snowboarding when winter rolls in. Here's something you might not expect: Despite being in a sunny state, this region deals with some of the driest conditions, which has pushed locals to get creative with water conservation efforts over the years.

Frequently Asked Questions

Where is area code 840?
Area code 840 serves San Bernardino and surrounding communities in California, including Chino, Chino Hills, Claremont, Colton, Diamond Bar and 13 more. It is in the Pacific time zone.
What cities are in area code 840?
Area code 840 covers 18 cities in California: Chino, Chino Hills, Claremont, Colton, Diamond Bar, Fontana, Highland, Loma Linda, Montclair, Ontario, and 8 more
What time zone is 840?
Area code 840 is in the Pacific time zone (UTC-8).
When was area code 840 created?
Area code 840 was established in 2021 as an overlay to provide additional numbers for the region.
Is 840 a legitimate area code?
Yes, 840 is a valid, active area code assigned to San Bernardino, California. However, scammers can spoof any area code, so receiving a call from 840 doesn't guarantee the caller is actually in this area.

Why was the 840 area code introduced in 2021 for San Bernardino County?

The 840 area code was created as an overlay to meet the growing demand for phone numbers in the region due to rapid population expansion. This helped accommodate new residents and businesses in areas like Fontana and Colton without disrupting existing services.

What outdoor activities are popular in the cities served by area code 840?

Hiking and mountain biking are common in the nearby San Bernardino Mountains, accessible from cities like Highland. Fontana offers opportunities for motorsports at the Auto Club Speedway, drawing enthusiasts from the area.

How does the overlay nature of area code 840 affect local phone users in Chino and surrounding areas?

As an overlay on existing codes, 840 requires ten-digit dialing for all local calls, which helps manage the increased need for numbers in Chino and Diamond Bar. This change supports the area's development while allowing residents to keep their current phone numbers.

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