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The Commemorative Quarter for California





Welcome to San Dimas ...

The city of San Dimas is located in Los Angeles County<1>.

While we don't have a date for the founding of San Dimas, you might consider that their post office opened  in 1888.

The city was incorporated August 4, 1960.

From the  Census Estimates for 2019, San Dimas has a population of 33,534 people<2> (see below for details).

San Dimas is 960 feet [293 m] above sea level.<3>.

Time Zone: San Dimas lies in the Pacific Time Zone (PST/PDT) and observes daylight saving time

Area Codes for San Dimas: 909 & 840<4>

The ZIP code for San Dimas: 91773<5>

Population Details ...

Taken from the 2019 Census Estimates, San Dimas had an population of 33,534 people. This is an increase of 0.49% since the 2010 Census (or a decrease of 4.13% since the 2000 Census).

At the time of the 2010 Census, San Dimas had a population of 33,371 people. This makes San Dimas the county's 54th most populous community.

The population of San Dimas represents 0.09% of the total population of California (which has 37,253,956 people), making it the state's 221st most populous community.

With a 2010 count of 33,371 people, the population of San Dimas decreased 4.6% from the 2000 Census (which had a count of 34,980 people).

More information can be found on the Census Page for San Dimas.

Websites for San Dimas ...

Official Website: www.cityofsandimas.com/

Communities near San Dimas ...

We have created a list of 10 communities that are near San Dimas.

To Help With Your Genealogy Research ...

We have a couple of sections for those tracing their genealogy.

We created a list of cemeteries that are in the area around San Dimas. Our list includes the location of those cemeteries and we provide an overhead view. See our Cemetery List for San Dimas.

Using the information from an 1895 Atlas, we've created a list of communities that were in the area of San Dimas. Our list includes information such as whether the 1895 community had a post office or railroad service. See our List of 1890's Communities around San Dimas.

We also have a detailed list of newspapers that have been published in the area around San Dimas. Our list includes 7 papers. See our Newspapers Page for San Dimas.

TripAdvisor Tourism Pages for San Dimas ...

Looking for more information about San Dimas? A wonderful source is the TripAdvisor website. We always start with the TripAdvisor Tourism page, where you can read an overview with links that will help you find lodging, restaurants and attractions.

In addition to the Tourism page for San Dimas, there are neighboring communities that also have Tourism pages. More information about those communities can be found on our TripAdvisor Page for San Dimas.

Adding San Dimas to Our Gazetteer ...

We originally found mention of San Dimas in both the FIPS-55 and the GNIS. For more information, see the FIPS and GNIS Codes sections on our Miscellaneous Page.

From our notes, the earliest published mention we've found for San Dimas was in the document titled List of Post Offices from Cameron Blevins and Richard Helbock.<7>

X2X - From that list, the San Dimas post office opened in 1888.

We also found San Dimas in the book titled Business Atlas and Shippers' Guide (1895).

For more details, see References and Mentions for San Dimas.

The official website for San Dimas: www.cityofsandimas.com/

The official website for Los Angeles County: www.lacounty.info/

The official website for State of California: https://www.ca.gov/

Footnotes ...

<1>If you're interested in how the shape of California's counties, including Los Angeles, have changed over time, we recommend the Atlas of Historical County Boundaries.
<2>Population counts have been provided by the U.S. Census Bureau. For more detail, please visit our Census Page for San Dimas.
<3>The elevation is an estimate for the area around San Dimas - it will be higher in some places and lower in others.
<4>When there's a risk of an area code running out of phone numbers, an 'Overlay Area Code' is created that has the same geographic boundaries as the existing area code. In this case, the 909 code has been Overlayed with the 840 area code. New phone numbers in the San Dimas area will be assigned with one of these codes: 909 or 840. As a result, placing a call in the San Dimas area will require 10-digit dialing (where you enter both the area code and then the phone number).
<5>ZIP Codes have been created by the United States Postal Service (USPS) as a way of grouping addresses to make delivery more efficient. The boundaries of the ZIP Code can be changed, re-assigned, eliminated or overlapped with other ZIP Codes. So keep in mind that any given ZIP Code is only 'loosely' associated with a city (such as San Dimas). When looking for a ZIP Code, whether San Dimas or elsewhere, it's always best to check the website of the United States Postal Service (USPS).
<6>While we're fans and frequent users of TripAdvisor, you should know that we're also members of the TripAdvisor affiliate program.
<7>A copy of their list with background information can be found at:

      https://cblevins.github.io/us-post-offices/data-biography/




 

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This page was last modified/updated: 28 Apr 2025