San Ramon's population was 84,605 per the 2020 census,[9] making it the 4th largest city in Contra Costa County, behind Concord, Richmond and Antioch.

Major annual events include the Art and Wind Festival on Memorial Day weekend and the Run for Education in October.

The lands now occupied by the City of San Ramon were formerly inhabited by Seunen people, an Ohlone/Costanoan group who built their homes near creeks.

[12] Amador named San Ramón (Spanish for 'Saint Raymond') after a Native American vaquero who tended mission sheep on the land.

In 1850, the first permanent American settlers, Leo and Mary Jane Norris, purchased the northwest corner of Amador's Rancho San Ramon, near the intersection of present-day Bollinger Canyon Road and Crow Canyon Road.

[12] The tracks for the San Ramon Branch Line of the Southern Pacific Railroad were laid down and completed in 1891.

By 1986, Contra Costa County had obtained the railroad right-of-way and the Iron Horse Regional Trail was established along its path.

The Las Trampas Regional Wilderness borders San Ramon's extreme northwest, at the northern end of Bollinger Canyon.

The smaller Bishop Ranch Regional Preserve straddles San Ramon's western border, located approximately between Interstate 680 and the Alameda County line.

Summers can range from warm to hot and dry, while winters are mild or cool, wet and rather short.

Fog can be infrequent but occurs normally in the western reaches of the city, at the eastern mouth of Crow Canyon, through which marine weather patterns funnel in from the San Francisco Bay via Castro Valley.

Bishop Ranch, a master-planned office park development, with some retail elements, began major construction in the early 1980s, and provides a healthy tax base for the city.

Bishop Ranch covers the vast majority of "Central San Ramon", which is the large square formed by Freeway 680 on the west, Crow Canyon Road on the north, Iron Horse trail on the east, and Bollinger Canyon Road on the south (though several complexes are south of Bollinger).

In December 2016, the Ligier EZ-10 began use in the first autonomous vehicle passenger shuttle route in North America, looping through Bishop Ranch Office Park, with on-sight operation and maintenance by First Transit.

The City Center has a variety of shops, including furniture, clothing, food, and an indoor movie theater.

[28] The city center was designed by international architectural firm Renzo Piano Building Workshop.

[30] Forest Home Farms in San Ramon is listed on the National Register of Historic Places.

[32] This 16-acre park includes a play area, a BMX course, a picnic area, a bocce ball court, horseshoe courts, a ball field, a dog park, restrooms and water fountains (including a doggy water fountain).

As of 2025, the Mayor is Mark Armstrong, and the other City Councilmembers are Richard Adler, Robert Jweinat, Marisol Rubio, and Sridhar Verose.

[47] Local bus service in the San Ramon Valley is provided primarily by County Connection (Central Contra Costa Transit Authority, or CCCTA).

San Ramon is located near Buchanan Field Airport and Livermore Municipal Airport, though Buchanan Field only flies to destinations in Greater Los Angeles, and Livermore has no regularly scheduled commercial service.