Census tract · Contra Costa County
Census Tract 3551.09, Contra Costa County, California
Census Tract 3551.09, GEOID 06013355109, in Contra Costa County, California, entirely within Antioch. 7,037 residents in the ACS 2020-2024 5-year estimates (±927); the 2020 Census counted 7,167.
Residents, 2020-2024
7,037
±927 (90% margin)
2020 Census count: 7,167
Median household income
$120,842
±$12,119 (90% margin)
Contra Costa County: $127,229
Median home value
$683,800
±$39,249 (90% margin)
Contra Costa County: $866,800
Median gross rent
$3,036
±$1,615 (90% margin)
Contra Costa County: $2,375
Where is Census Tract 3551.09?
Census Tract 3551.09 is one of 242 census tracts in Contra Costa County, California. It covers 1.15 square miles of land, 6,227 residents per square mile in 2020. Its GEOID, 06013355109, names it uniquely (how tract numbers and GEOIDs work).
| Place | Share of the tract |
|---|---|
| Antioch | 100% |
6 census tracts border Census Tract 3551.09: Tract 3080.01 ($80,539), Tract 3551.07 ($151,845), Tract 3551.10 ($138,269), Tract 3551.11 ($99,543), Tract 3551.18 ($113,194) and Tract 3551.20 ($102,485). The figure in brackets is each tract's median household income.
Whether a tract counts as low- or moderate-income for bank lending (the Community Reinvestment Act) is set by the FFIEC against its metro area's family income: look it up in the FFIEC census geocoder.
Source: 2024 Gazetteer and 2020 block assignment files, U.S. Census Bureau · Census reference files
How many people live in Census Tract 3551.09?
The 2020-2024 American Community Survey puts Census Tract 3551.09's population at 7,037 (±927) in 2,014 households; the 2020 Census counted 7,167 residents and 2,221 housing units.
| Measure | Tract 3551.09 | Antioch |
|---|---|---|
| Total population | 7,037 ±927 | 116,477 |
| Households | 2,014 ±202 | 37,381 |
| Average household size | 3.44 ±0.33 | 3.09 |
| Housing units | 2,186 ±240 | 38,629 |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); 2020 Census P.L. 94-171 · Check it at data.census.gov
Who lives in Census Tract 3551.09?
The median resident of Census Tract 3551.09 is 38.4 years old; 26.1% are under 18 and 17.3% are 65 or older. The largest group is Hispanic or Latino residents (of any race) at 24.2%, then non-Hispanic Asian residents at 23.2%. 26.7% of residents were born outside the United States.
| Measure | Tract 3551.09 | Antioch |
|---|---|---|
| Median age | 38.4 ±3.0 | 38.4 |
| Under 18 years | 26.1% ±5.6 pts | 22.8% |
| 65 years and over | 17.3% ±4.0 pts | 14.3% |
| Hispanic or Latino (any race) | 24.2% ±5.2 pts | 35.6% |
| White alone, not Hispanic | 20.4% ±8.0 pts | 23.4% |
| Black or African American alone, not Hispanic | 15.0% ±8.7 pts | 18.2% |
| Asian alone, not Hispanic | 23.2% ±9.9 pts | 13.9% |
| American Indian and Alaska Native alone, not Hispanic | 1.7% ±2.1 pts | 0.5% |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 11.1% ±8.0 pts | 1.1% |
| Two or more races, not Hispanic | 4.5% ±3.3 pts | 6.8% |
| Some other race alone, not Hispanic | 0.0% ±0.6 pts | 0.5% |
| Born outside the United States | 26.7% ±7.3 pts | 24.6% |
| Speak a language other than English at home (age 5+) | 39.3% ±7.8 pts | 37.7% |
| Civilian veterans (age 18+) | 4.2% ±1.9 pts | 4.8% |
| With a disability | 13.7% ±4.0 pts | 15.2% |
| No health insurance coverage | 1.9% ±1.5 pts | 6.4% |
| High school graduate or higher (age 25+) | 88.3% ±5.4 pts | 85.3% |
| Bachelor's degree or higher (age 25+) | 33.0% ±8.6 pts | 23.9% |
| Graduate or professional degree (age 25+) | 11.0% ±4.4 pts | 6.7% |
| Lived in the same house a year earlier | 92.4% ±4.0 pts | 90.4% |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profiles DP02, DP05) · Check it at data.census.gov
What do households in Census Tract 3551.09 earn?
Half of the 2,014 households in Census Tract 3551.09 earn less than $120,842 a year (±$12,119), against $127,229 across Contra Costa County: 135th highest of the county's 239 tracts with a reliable estimate.
| Measure | Tract 3551.09 | Antioch |
|---|---|---|
| Median household income | $120,842 ±$12,119 | $97,465 |
| Mean household income | $125,818 ±$16,136 | $124,206 |
| Per capita income | $38,685 ±$6,420 | $41,008 |
| People below the poverty line | 13.6% ±9.6 pts | 11.4% |
| Children under 18 below the poverty line | 14.4% ±15.0 pts | 16.3% |
| Households receiving SNAP | 4.1% ±3.7 pts | 14.2% |
| Households with a computer | 98.7% ±1.5 pts | 97.7% |
| Households with a broadband subscription | 95.8% ±3.7 pts | 95.8% |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
What does housing cost in Census Tract 3551.09?
Owners occupy 72.1% of Census Tract 3551.09's occupied homes and renters 27.9%. The median owner-occupied home is valued at $683,800 by its owner (±$39,249). The median renter pays $3,036 a month including utilities, and 49.3% of renters pay 35% or more of their income on rent.
| Measure | Tract 3551.09 | Antioch |
|---|---|---|
| Median home value (owner-occupied) | $683,800 ±$39,249 | $629,700 |
| Median gross rent | $3,036 ±$1,615 | $2,278 |
| Renters paying 35% or more of income on rent | 49.3% ±18.9 pts | 55.7% |
| Median monthly owner costs, with a mortgage | $2,938 ±$517 | $2,768 |
| Owner-occupied homes | 72.1% ±8.8 pts | 63.6% |
| Renter-occupied homes | 27.9% ±8.8 pts | 36.4% |
| Housing units | 2,186 ±240 | 38,629 |
| Single-family detached homes | 90.5% ±7.1 pts | 78.3% |
| Mobile homes | 0.7% ±1.2 pts | 1.1% |
| Built 2020 or later | 0.0% ±1.9 pts | 2.5% |
| Built 2010 to 2019 | 2.6% ±2.8 pts | 4.5% |
| Built 1939 or earlier | 0.3% ±1.3 pts | 2.4% |
| Households with no vehicle | 1.4% ±1.7 pts | 5.2% |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP04) · Check it at data.census.gov
How do people in Census Tract 3551.09 get to work?
73.9% of Census Tract 3551.09's workers drive alone and 9.5% work from home. The average trip to work takes 45.5 minutes. The unemployment rate in 2020-2024 averaged 10.5%.
| Measure | Tract 3551.09 | Antioch |
|---|---|---|
| In the labor force (age 16+) | 63.1% ±5.6 pts | 65.0% |
| Unemployment rate | 10.5% ±6.7 pts | 7.4% |
| Drove alone to work | 73.9% ±7.0 pts | 65.6% |
| Carpooled | 6.0% ±4.4 pts | 14.9% |
| Public transportation | 9.7% ±6.5 pts | 4.8% |
| Walked | 0.0% ±1.4 pts | 0.9% |
| Worked from home | 9.5% ±3.8 pts | 12.7% |
| Mean travel time to work | 45.5 min ±6.1 | 42.0 min |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
How does Census Tract 3551.09 compare with the other tracts in Contra Costa County?
Among Contra Costa County's tracts with a reliable estimate, Census Tract 3551.09 ranks as shown below (1 = highest).
| Measure | In Contra Costa County | In Antioch |
|---|---|---|
| Population | 28th of 241 | 5th of 21 |
| Residents per square mile | 81st of 241 | 10th of 21 |
| Median household income | 135th of 239 | 5th of 21 |
| Per capita income | 193rd of 241 | 12th of 21 |
| Median home value | 155th of 236 | 5th of 21 |
| Median gross rent | 65th of 236 | 7th of 21 |
| Bachelor's degree or higher | 160th of 239 | 5th of 21 |
| Median age | 163rd of 241 | 14th of 21 |
| Owner-occupied share | 131st of 240 | 9th of 21 |
The tracts next to it on Contra Costa County's income ladder
| Tract | Rank | Median household income |
|---|---|---|
| Tract 3332 | 132nd | $123,964±$23,178 · within the margin of this tract |
| Tract 3331.02 | 133rd | $122,982±$10,227 · within the margin of this tract |
| Tract 3560.02 | 134th | $121,275±$27,170 · within the margin of this tract |
| Tract 3551.09 | 135th | $120,842±$12,119 |
| Tract 3340.01 | 136th | $120,208±$37,985 · within the margin of this tract |
| Tract 3080.02 | 137th | $119,896±$19,286 · within the margin of this tract |
| Tract 3031.06 | 138th | $119,806±$47,459 · within the margin of this tract |
"Within the margin": the two incomes differ by less than their combined 90% margins, so the survey cannot say which is higher and the ranks between them are not firm.
Source: PlainCities ranks computed from the American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) · How ranks are computed
How reliable are the figures for Census Tract 3551.09?
1 of the 18 figures for Census Tract 3551.09 on this page carries a coefficient of variation over 40% and is marked with a ring: they come from a small sample, so read them as rough.
A census tract's figures rest on a few hundred sampled households over five years, so its margins are wider than a city's. Two tracts differ only when the gap between them is larger than their combined 90% margin (the square root of the sum of the two squared margins). How to read a margin of error.
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026): margins of error as published · Check it at data.census.gov
How these figures are made: methodology and release checks · reading a margin of error · every state · corrections