Jefferson County Demographics

A map of Jefferson County's Population by Race

Race	2024 Pop	2020 Pop	2024 %	2020 %
White	16,710	16,549	91.1%	90.1%
Multiracial	733	932	4.0%	5.1%
Hispanic	648	567	3.5%	3.1%
Native American/Other	131	180	0.7%	1.0%
Black	82	99	0.4%	0.5%
Asian	45	41	0.2%	0.2%

Jefferson County, Kansas has an estimated population of 18,349, a less than 1% change from the 18,368 recorded in the 2020 Census. The population is 91.1% White, 4.0% Multiracial, 3.5% Hispanic, 0.7% Native American/Other, 0.4% Black, and 0.2% Asian. This demographic dot map shows the population of Jefferson County, with one dot drawn for each person counted by the Census, color-coded by race.

Jefferson has become less racially diverse since the 2020 Census. It is considerably less diverse than Kansas overall. Demographers use a diversity index to measure the probability that two randomly selected individuals belong to different racial or ethnic groups. In Jefferson County, that probability was 18.5% in 2020 and 16.8% in the most recent ACS estimates.

Jefferson County is ranked the 30th most populous county in Kansas, out of 105 counties. Jefferson County was ranked the 30th most populous county in the 2020 Census.

Jefferson County's White Population

16,710 residents of Jefferson County, or 91.1% of the population, identify as White. The share of White residents in Jefferson County is significantly higher than in Kansas overall, where 72.7% of the population is White. Jefferson County ranks 31st statewide in terms of White residents as a share of the population, out of 105 counties.

Since the 2020 Census, Jefferson County's White population has remained roughly the same. White residents' share of Jefferson County's population has increased from 90.1% to 91.1%.

Jefferson County is more White than neighboring Atchison County (86.7% White), Leavenworth County (77.4% White), Douglas County (76% White), Shawnee County (71% White), and Jackson County (81.6% White).

Jefferson County's Black Population

82 residents of Jefferson County, or 0.4% of the population, identify as Black. The share of Black residents in Jefferson County is slightly lower than in Kansas overall, where 5.2% of the population is Black. Jefferson County ranks 60th statewide in terms of Black residents as a share of the population, out of 105 counties.

Since the 2020 Census, Jefferson County's Black population has declined by an estimated 17.2%. Black residents' share of Jefferson County's population has remained roughly unchanged at 0.4%.

Jefferson County is less Black than neighboring Atchison County (3.5% Black), Leavenworth County (6.8% Black), Douglas County (4.2% Black), Shawnee County (6.6% Black), and Jackson County (0.7% Black).

Jefferson County's Asian Population

45 residents of Jefferson County, or 0.2% of the population, identify as Asian. The share of Asian residents in Jefferson County is slightly lower than in Kansas overall, where 2.9% of the population is Asian. Jefferson County ranks 85th statewide in terms of Asian residents as a share of the population, out of 105 counties.

Since the 2020 Census, Jefferson County's Asian population has grown by an estimated 9.8%. Asian residents' share of Jefferson County's population has remained roughly unchanged at 0.2%.

Jefferson County is less Asian than neighboring Atchison County (0.3% Asian), Leavenworth County (1.3% Asian), Douglas County (4.3% Asian), Shawnee County (1.3% Asian), and Jackson County (0.5% Asian).

Jefferson County's Hispanic Population

648 residents of Jefferson County, or 3.5% of the population, identify as Hispanic. The share of Hispanic residents in Jefferson County is considerably lower than in Kansas overall, where 13.6% of the population is Hispanic. Jefferson County ranks 81st statewide in terms of Hispanic residents as a share of the population, out of 105 counties.

Since the 2020 Census, Jefferson County's Hispanic population has grown by an estimated 14.3%. Hispanic residents' share of Jefferson County's population has remained roughly unchanged at 3.5%.

Jefferson County is less Hispanic than neighboring Atchison County (3.8% Hispanic), Leavenworth County (7.6% Hispanic), Douglas County (7.2% Hispanic), Shawnee County (13.8% Hispanic), and Jackson County (5.8% Hispanic).

Jefferson County's Native American/Other Population

131 residents of Jefferson County, or 0.7% of the population, identify as American Indian/Alaska Native/Native Hawaiian/Pacific Islander/Other. The share of Native American/Other residents in Jefferson County is comparable to the share in Kansas overall, where 0.9% of the population is Native American/Other. Jefferson County ranks 33rd statewide in terms of Native American/Other residents as a share of the population, out of 105 counties.

Since the 2020 Census, Jefferson County's Native American/Other population has declined by an estimated 27.2%. Native American/Other residents' share of Jefferson County's population has remained roughly unchanged at 0.7%.

Jefferson County is more Native American/Other than neighboring Atchison County (0.3% Native American/Other). Jefferson County is less Native American/Other than neighboring Leavenworth County (1% Native American/Other), Douglas County (1.5% Native American/Other), Shawnee County (1% Native American/Other), and Jackson County (5.5% Native American/Other).

Jefferson County's Multiracial Population

733 residents of Jefferson County, or 4.0% of the population, identify as Multiracial. The share of Multiracial residents in Jefferson County is comparable to the share in Kansas overall, where 4.8% of the population is Multiracial. Jefferson County ranks 25th statewide in terms of Multiracial residents as a share of the population, out of 105 counties.

Since the 2020 Census, Jefferson County's Multiracial population has declined by an estimated 21.4%. Multiracial residents' share of Jefferson County's population has decreased from 5.1% to 4.0%.

Jefferson County is less Multiracial than neighboring Atchison County (5.4% Multiracial), Leavenworth County (5.9% Multiracial), Douglas County (6.8% Multiracial), Shawnee County (6.3% Multiracial), and Jackson County (5.9% Multiracial).

Sources: Most recent population estimates are from the 2020-2024 American Community Survey 5-Year Estimates. 2020 population counts and map data are from 2020 Census State Redistricting Data. Geographic data are from Census TIGER/Line Shapefiles.