The 840 area code is the newest overlay for California’s Inland Empire, sharing the same territory long served by 909. The change guarantees a steady flow of phone numbers, but it also cements ten digit (or 1 + ten digit) dialing for every local call. Here’s the essentials.
New 840 Overlay
Regulators opted for an overlay layering 840 on top of 909 instead of carving the region into smaller zones. Your existing 909 number remains exactly the same; only new lines may receive 840. Because two codes now cover one map, every local call must include the area code plus the seven digit number.
840 / 909 Area Code Region
The combined overlay spans most of California’s Inland Empire and far eastern Los Angeles County, including
- San Bernardino, Ontario, Rancho Cucamonga, Fontana, Redlands, Rialto
- Pomona, Claremont, Diamond Bar, Chino, Chino Hills, Upland, Montclair
- Big Bear Lake, Yucaipa, Highland and neighboring communities across San Bernardino, Riverside, and eastern L.A. counties
Dialing Rules
Landlines: Dial 1 + area code + phone number (11 digits total).
Mobile phones: Dial area code + phone number (10 digits) or 1 + area code + number either works.
Seven digit dialing no longer completes a call.
Mandatory ten digit dialing has been in force since January 23 2021.
Key Dates for the 840 Roll Out
| Date | Milestone |
|---|---|
| July 25 2020 | Permissive 7 /10 digit dialing period begins |
| January 23 2021 | Mandatory 10 /11 digit dialing for all calls |
| February 23 2021 | First 840 numbers become available |
What Stays the Same
- Your current 909 number does not change.
- Local calling areas and pricing remain identical 840 carries no extra fees.
- Three digit services (911, 211, 311, etc.) still dial with three digits.
- Long distance rules and toll rates remain unchanged.
Frequently Asked Questions
Why add 840 instead of splitting the map?
An overlay keeps residents and businesses from having to change long standing numbers while still expanding numbering capacity.
Will caller ID look odd with 840?
No 840 simply signals a newer assignment within the same Inland Empire footprint.
Do mobile users have to dial “1”?
Most carriers complete calls with either ten or eleven digits; landlines generally need the leading “1.”
Does the overlay raise call charges?
No. Rate center boundaries and tariffs stay exactly the same.
