840 area code: San Bernardino, Pomona, Ontario

Updated: 10/16/2026

840 is the area code for San Bernardino, Pomona, Ontario. Phone numbers with this area code are written as (840) XXX-XXXX.

840 area code - San Bernardino, Pomona, Ontario

Area code840
AreaSan Bernardino, Pomona, Ontario
State or regionCalifornia
Time zonePacific Time (PT)
Number format(840) XXX-XXXX
International format+1 840-XXX-XXXX

Overlay: the same area is also served by area code 909, so local calls need all 10 digits.

An area code does not prove where the caller is. People keep their number when they move or switch carriers, internet phone (VoIP) services hand out numbers in any area code, and scammers often fake a local area code (neighbor spoofing) to get you to pick up.

Missed call from a number starting with 840 - what to do

  • Look up the full number in the search below to see reviews and reports from other people.
  • Never read out one-time passcodes, card details or online banking passwords over the phone. No real bank, government agency or police department will ask you to move money to a "safe account" or pay with gift cards.
  • Forward spam texts to 7726 (SPAM) for free and report scams to the FTC at reportfraud.ftc.gov. Internet-based fraud can also be reported to the FBI at ic3.gov.

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