Stephenson County Demographics

A map of Stephenson County's Population by Race

Race	2024 Pop	2020 Pop	2024 %	2020 %
White	34,544	35,405	78.9%	79.3%
Black	3,701	4,374	8.5%	9.8%
Multiracial	2,461	2,045	5.6%	4.6%
Hispanic	2,457	2,254	5.6%	5.1%
Asian	361	306	0.8%	0.7%
Native American/Other	244	246	0.6%	0.6%

Stephenson County, Illinois has an estimated population of 43,768, a slight decrease from the 44,630 recorded in the 2020 Census. The population is 78.9% White, 8.5% Black, 5.6% Hispanic, 5.6% Multiracial, 0.8% Asian, and 0.6% Native American/Other. This demographic dot map shows the population of Stephenson County, with one dot drawn for each person counted by the Census, color-coded by race.

Stephenson has become slightly more racially diverse since the 2020 Census. It is considerably less diverse than Illinois overall. Demographers use a diversity index to measure the probability that two randomly selected individuals belong to different racial or ethnic groups. In Stephenson County, that probability was 35.6% in 2020 and 36.4% in the most recent ACS estimates.

Stephenson County is ranked the 33rd most populous county in Illinois, out of 102 counties. Stephenson County was ranked the 33rd most populous county in the 2020 Census.

Stephenson County's White Population

34,544 residents of Stephenson County, or 78.9% of the population, identify as White. The share of White residents in Stephenson County is significantly higher than in Illinois overall, where 58.1% of the population is White. Stephenson County ranks 77th statewide in terms of White residents as a share of the population, out of 102 counties.

Since the 2020 Census, Stephenson County's White population has declined by an estimated 2.4%. White residents' share of Stephenson County's population has remained roughly unchanged at 78.9%.

Stephenson County is more White than neighboring Winnebago County (63.8% White). Stephenson County is less White than neighboring Green County (92% White), Carroll County (87.8% White), Ogle County (83% White), and Jo Daviess County (91.9% White).

Stephenson County's Black Population

3,701 residents of Stephenson County, or 8.5% of the population, identify as Black. The share of Black residents in Stephenson County is slightly lower than in Illinois overall, where 13.3% of the population is Black. Stephenson County ranks 17th statewide in terms of Black residents as a share of the population, out of 102 counties.

Since the 2020 Census, Stephenson County's Black population has declined by an estimated 15.4%. Black residents' share of Stephenson County's population has decreased from 9.8% to 8.5%.

Stephenson County is more Black than neighboring Green County (0.8% Black), Carroll County (3.9% Black), Ogle County (1.2% Black), and Jo Daviess County (0.8% Black). Stephenson County is less Black than neighboring Winnebago County (11.6% Black).

Stephenson County's Asian Population

361 residents of Stephenson County, or 0.8% of the population, identify as Asian. The share of Asian residents in Stephenson County is lower than in Illinois overall, where 5.9% of the population is Asian. Stephenson County ranks 40th statewide in terms of Asian residents as a share of the population, out of 102 counties.

Since the 2020 Census, Stephenson County's Asian population has grown by an estimated 18.0%. Asian residents' share of Stephenson County's population has remained roughly unchanged at 0.8%.

Stephenson County is more Asian than neighboring Green County (0.6% Asian), Ogle County (0.6% Asian), and Jo Daviess County (0.5% Asian). Stephenson County is less Asian than neighboring Winnebago County (2.9% Asian).

Stephenson County's Hispanic Population

2,457 residents of Stephenson County, or 5.6% of the population, identify as Hispanic. The share of Hispanic residents in Stephenson County is considerably lower than in Illinois overall, where 18.8% of the population is Hispanic. Stephenson County ranks 32nd statewide in terms of Hispanic residents as a share of the population, out of 102 counties.

Since the 2020 Census, Stephenson County's Hispanic population has grown by an estimated 9.0%. Hispanic residents' share of Stephenson County's population has increased from 5.1% to 5.6%.

Stephenson County is more Hispanic than neighboring Green County (4.2% Hispanic), Carroll County (5.3% Hispanic), and Jo Daviess County (4.2% Hispanic). Stephenson County is less Hispanic than neighboring Ogle County (11.9% Hispanic), and Winnebago County (15.5% Hispanic).

Stephenson County's Native American/Other Population

244 residents of Stephenson County, or 0.6% of the population, identify as American Indian/Alaska Native/Native Hawaiian/Pacific Islander/Other. The share of Native American/Other residents in Stephenson County is comparable to the share in Illinois overall, where 0.5% of the population is Native American/Other. Stephenson County ranks 20th statewide in terms of Native American/Other residents as a share of the population, out of 102 counties.

Since the 2020 Census, Stephenson County's Native American/Other population has remained roughly the same. Native American/Other residents' share of Stephenson County's population has remained roughly unchanged at 0.6%.

Stephenson County is more Native American/Other than neighboring Green County (0.3% Native American/Other), Carroll County (0.5% Native American/Other), Ogle County (0.4% Native American/Other), Winnebago County (0.5% Native American/Other), and Jo Daviess County (0.5% Native American/Other).

Stephenson County's Multiracial Population

2,461 residents of Stephenson County, or 5.6% of the population, identify as Multiracial. The share of Multiracial residents in Stephenson County is slightly higher than in Illinois overall, where 3.4% of the population is Multiracial. Stephenson County ranks 15th statewide in terms of Multiracial residents as a share of the population, out of 102 counties.

Since the 2020 Census, Stephenson County's Multiracial population has grown by an estimated 20.3%. Multiracial residents' share of Stephenson County's population has increased from 4.6% to 5.6%.

Stephenson County is more Multiracial than neighboring Green County (2.1% Multiracial), Carroll County (1.7% Multiracial), Ogle County (2.9% Multiracial), and Jo Daviess County (2.2% Multiracial). Stephenson County is less Multiracial than neighboring Winnebago County (5.8% 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.