According to theUnited States Census Bureau, the city has a total area of 4.1 square miles (11 km2), of which 4.0 square miles (10 km2) is land and 0.06 square miles (0.16 km2) (1.48%) is water.
The city is adjacent toSuisun Marsh, at 84,000 acres (34,000 ha) the largest contiguous estuarine marsh remaining on the west coast of North America.
The census reported that 99.8% of the population lived in households, 0.2% lived in non-institutionalized group quarters, and 0.1% were institutionalized.[13]
There were 9,316 households, out of which 39.6% included children under the age of 18, 51.9% were married-couple households, 7.2% werecohabiting couple households, 25.9% had a female householder with no partner present, and 15.0% had a male householder with no partner present. 15.9% of households were one person, and 6.3% were one person aged 65 or older. The average household size was 3.16.[13] There were 7,283families (78.2% of all households).[14]
The age distribution was 23.3% under the age of 18, 9.2% aged 18 to 24, 28.7% aged 25 to 44, 25.2% aged 45 to 64, and 13.6% who were 65years of age or older. The median age was 36.7years. For every 100 females, there were 94.8 males.[13]
There were 9,522 housing units at an average density of 2,377.5 units per square mile (918.0 units/km2), of which 9,316 (97.8%) were occupied. Of these, 67.5% were owner-occupied, and 32.5% were occupied by renters.[13]
In 2023, the US Census Bureau estimated that the median household income was $97,083, and theper capita income was $37,217. About 6.4% of families and 8.7% of the population were below the poverty line.[15]
The2010 United States census[16] reported that Suisun City had a population of 28,111. The population density was 6,752.3 inhabitants per square mile (2,607.1/km2). The racial makeup of Suisun City was 10,805 (38.4%)White, 5,713 (20.3%)African American, 196 (0.7%)Native American, 5,348 (19.0%)Asian, 340 (1.2%)Pacific Islander, 2,898 (10.3%) fromother races, and 2,811 (10.0%) from two or more races.Hispanic orLatino of any race were 6,753 persons (24.0%).
The Census reported that 28,067 people (99.8% of the population) lived in households, 27 (0.1%) lived in non-institutionalized group quarters, and 17 (0.1%) were institutionalized.
There were 8,918 households, of which 4,013 (45.0%) had children under the age of 18 living in them, 4,856 (54.5%) wereopposite-sex married couples living together, 1,482 (16.6%) had a female householder with no husband present, 624 (7.0%) had a male householder with no wife present. There were 596 (6.7%)unmarried opposite-sex partnerships, and 66 (0.7%)same-sex married couples or partnerships. 1,443 households (16.2%) were made up of individuals, and 350 (3.9%) had someone living alone who was 65 years of age or older. The average household size was 3.15. There were 6,962families (78.1% of all households); the average family size was 3.52.
7,737 people (27.5%) were under the age of 18, 2,950 people (10.5%) aged 18 to 24, 7,850 people (27.9%) aged 25 to 44, 7,418 people (26.4%) aged 45 to 64, and 2,156 people (7.7%) who were 65 years of age or older. The median age was 33.0 years. For every 100 females, there were 96.9 males. For every 100 females age 18 and over, there were 92.9 males.
There were 9,454 housing units at an average density of 2,270.9 units per square mile (876.8 units/km2), of which 6,184 (69.3%) were owner-occupied, and 2,734 (30.7%) were occupied by renters. The homeowner vacancy rate was 3.0%; the rental vacancy rate was 5.9%. 19,372 people (68.9% of the population) lived in owner-occupied housing units and 8,695 people (30.9%) lived in rental housing units.
In 1888, a fire destroyed much of downtown Suisun, including many city landmarks, such as the Robert Hotel, Crowley's saloon, the Union Hotel, and the Orkel grain warehouses. Citizens considered abandoning the city after the devastation, but instead decided to rebuild and raise money to construct a waterworks system that would allow them to fight future fires more effectively.[18]
In the 1960s and 1970s, Suisun City experienced rapid growth as the San Francisco Bay Area's suburban ring expanded to the formerly rural Solano County. Also in the 1960s,Interstate 80 was constructed two miles (3.2 km) outside the city, effectively moving commercial traffic away from railways and water conveyance.
In January 2025, the city of Suisun City announced that it was investigating expanding to lands to the east, effectively annexing much ofCalifornia Forever.[19]
^"THE "SOLANO." The New Route Between Benicia and Martinez in Operation".cdnc.ucr.edu. Daily Alta California, Volume 31, Number 10851. December 30, 1879. RetrievedJune 21, 2021.Sunday [28 Dec 1879], the first passenger train passed over the new route of the Central Pacific Railroad, crossing the strait at Benicia on the new ferry-boat Solano.