Census tract · Mercer County
Census Tract 31, Mercer County, New Jersey
Census Tract 31, GEOID 34021003100, in Mercer County, New Jersey, entirely within Lawrence Township, Mercer County. 4,276 residents in the ACS 2020-2024 5-year estimates (±632); the 2020 Census counted 4,516.
Residents, 2020-2024
4,276
±632 (90% margin)
2020 Census count: 4,516
Median household income
$69,235
±$21,730 (90% margin)
Mercer County: $100,645
Median home value
$299,500
±$26,798 (90% margin)
Mercer County: $377,700
Median gross rent
$1,537
±$292 (90% margin)
Mercer County: $1,623
Where is Census Tract 31?
Census Tract 31 is one of 84 census tracts in Mercer County, New Jersey. It covers 1.16 square miles of land, 3,903 residents per square mile in 2020. Its GEOID, 34021003100, names it uniquely (how tract numbers and GEOIDs work).
| Place | Share of the tract |
|---|---|
| Lawrence Township, Mercer County | 100% |
6 census tracts border Census Tract 31: Tract 18 ($57,734), Tract 29.02 ($97,167), Tract 32.01 ($117,179), Tract 32.02 ($122,540), Tract 34 ($67,807) and Tract 35 ($79,176). 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 31?
The 2020-2024 American Community Survey puts Census Tract 31's population at 4,276 (±632) in 1,699 households; the 2020 Census counted 4,516 residents and 1,885 housing units.
| Measure | Tract 31 | Lawrence Township, Mercer County |
|---|---|---|
| Total population | 4,276 ±632 | 32,313 |
| Households | 1,699 ±199 | 12,442 |
| Average household size | 2.51 ±0.26 | 2.41 |
| Housing units | 1,777 ±186 | 12,927 |
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 31?
The median resident of Census Tract 31 is 42.3 years old; 26.0% are under 18 and 17.5% are 65 or older. The largest group is non-Hispanic white residents at 54.2%, then Hispanic or Latino residents (of any race) at 27.5%. 43.0% of residents were born outside the United States.
| Measure | Tract 31 | Lawrence Township, Mercer County |
|---|---|---|
| Median age | 42.3 ±2.9 | 40.2 |
| Under 18 years | 26.0% ±4.9 pts | 18.8% |
| 65 years and over | 17.5% ±4.7 pts | 17.1% |
| Hispanic or Latino (any race) | 27.5% ±9.7 pts | 15.5% |
| White alone, not Hispanic | 54.2% ±9.3 pts | 54.1% |
| Black or African American alone, not Hispanic | 9.2% ±4.1 pts | 12.7% |
| Asian alone, not Hispanic | 7.6% ±7.1 pts | 14.5% |
| American Indian and Alaska Native alone, not Hispanic | 0.0% ±1.0 pts | 0.0% |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.0% ±1.0 pts | 0.0% |
| Two or more races, not Hispanic | 1.6% ±1.3 pts | 2.9% |
| Some other race alone, not Hispanic | 0.0% ±1.0 pts | 0.2% |
| Born outside the United States | 43.0% ±7.8 pts | 27.3% |
| Speak a language other than English at home (age 5+) | 61.6% ±11.1 pts | 35.9% |
| Civilian veterans (age 18+) | 2.4% ±2.4 pts | 1.7% |
| With a disability | 11.9% ±3.5 pts | 7.1% |
| No health insurance coverage | 11.6% ±4.7 pts | 5.4% |
| High school graduate or higher (age 25+) | 84.9% ±5.4 pts | 91.8% |
| Bachelor's degree or higher (age 25+) | 27.3% ±8.3 pts | 61.3% |
| Graduate or professional degree (age 25+) | 9.6% ±4.5 pts | 28.0% |
| Lived in the same house a year earlier | 91.6% ±4.4 pts | 83.0% |
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 31 earn?
Half of the 1,699 households in Census Tract 31 earn less than $69,235 a year (±$21,730), against $100,645 across Mercer County: 62nd highest of the county's 81 tracts with a reliable estimate. 7.0% of residents live below the poverty line.
| Measure | Tract 31 | Lawrence Township, Mercer County |
|---|---|---|
| Median household income | $69,235 ±$21,730 | $130,142 |
| Mean household income | $91,852 ±$11,999 | $160,293 |
| Per capita income | $37,010 ±$6,149 | $61,892 |
| People below the poverty line | 7.0% ±4.4 pts | 4.5% |
| Children under 18 below the poverty line | 12.9% ±10.6 pts | 6.0% |
| Households receiving SNAP | 11.4% ±5.2 pts | 3.0% |
| Households with a computer | 89.5% ±6.6 pts | 96.2% |
| Households with a broadband subscription | 84.2% ±7.9 pts | 93.6% |
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 31?
Owners occupy 67.2% of Census Tract 31's occupied homes and renters 32.8%. The median owner-occupied home is valued at $299,500 by its owner (±$26,798). The median renter pays $1,537 a month including utilities, and 60.2% of renters pay 35% or more of their income on rent.
| Measure | Tract 31 | Lawrence Township, Mercer County |
|---|---|---|
| Median home value (owner-occupied) | $299,500 ±$26,798 | $439,700 |
| Median gross rent | $1,537 ±$292 | $2,020 |
| Renters paying 35% or more of income on rent | 60.2% ±17.9 pts | 37.3% |
| Median monthly owner costs, with a mortgage | $2,242 ±$211 | $2,933 |
| Owner-occupied homes | 67.2% ±8.9 pts | 67.5% |
| Renter-occupied homes | 32.8% ±8.9 pts | 32.5% |
| Housing units | 1,777 ±186 | 12,927 |
| Single-family detached homes | 49.1% ±7.5 pts | 49.2% |
| Mobile homes | 0.0% ±2.5 pts | 0.0% |
| Built 2020 or later | 0.0% ±2.5 pts | 1.5% |
| Built 2010 to 2019 | 1.2% ±1.5 pts | 2.1% |
| Built 1939 or earlier | 14.7% ±5.6 pts | 7.8% |
| Households with no vehicle | 16.8% ±7.0 pts | 6.3% |
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 31 get to work?
63.3% of Census Tract 31's workers drive alone and 19.0% work from home. The average trip to work takes 26.8 minutes.
| Measure | Tract 31 | Lawrence Township, Mercer County |
|---|---|---|
| In the labor force (age 16+) | 59.9% ±5.4 pts | 67.4% |
| Unemployment rate | 2.9% ±2.6 pts | 6.0% |
| Drove alone to work | 63.3% ±9.3 pts | 54.8% |
| Carpooled | 10.4% ±7.3 pts | 7.7% |
| Public transportation | 3.3% ±2.3 pts | 4.7% |
| Walked | 2.0% ±3.1 pts | 3.7% |
| Worked from home | 19.0% ±8.5 pts | 28.1% |
| Mean travel time to work | 26.8 min ±5.2 | 28.7 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 31 compare with the other tracts in Mercer County?
Among Mercer County's tracts with a reliable estimate, Census Tract 31 ranks as shown below (1 = highest).
| Measure | In Mercer County |
|---|---|
| Population | 49th of 84 |
| Residents per square mile | 42nd of 84 |
| Median household income | 62nd of 81 |
| Per capita income | 54th of 83 |
| Median home value | 48th of 76 |
| Median gross rent | 51st of 76 |
| Poverty rate | 32nd of 47 |
| Bachelor's degree or higher | 54th of 79 |
| Median age | 35th of 84 |
| Owner-occupied share | 38th of 81 |
The tracts next to it on Mercer County's income ladder
| Tract | Rank | Median household income |
|---|---|---|
| Tract 37.07 | 59th | $73,750±$43,279 · within the margin of this tract |
| Tract 27.02 | 60th | $73,633±$4,653 · within the margin of this tract |
| Tract 6 | 61st | $69,950±$24,417 · within the margin of this tract |
| Tract 31 | 62nd | $69,235±$21,730 |
| Tract 34 | 63rd | $67,807±$14,109 · within the margin of this tract |
| Tract 30.09 | 64th | $65,886±$13,295 · within the margin of this tract |
| Tract 14.02 | 65th | $61,875±$17,959 · 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 31?
1 of the 18 figures for Census Tract 31 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