Ottawa, IL Demographics

A map of Ottawa's Population by Race

Race	2024 Pop	2020 Pop	2024 %	2020 %
White	15,229	15,607	82.6%	82.8%
Hispanic	1,861	1,789	10.1%	9.5%
Multiracial	714	731	3.9%	3.9%
Black	458	428	2.5%	2.3%
Asian	184	193	1.0%	1.0%
Native American/Other	1	92	0.0%	0.5%

Ottawa, Illinois has an estimated population of 18,447, a slight decrease from the 18,840 recorded in the 2020 Census. The population is 82.6% White, 10.1% Hispanic, 3.9% Multiracial, 2.5% Black, 1.0% Asian, and 0.0% Native American/Other. This demographic dot map shows the population of Ottawa, with one dot drawn for each person counted by the Census, color-coded by race.

Ottawa is about as racially diverse as it was in 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 Ottawa, that probability was 30.3% in 2020 and 30.6% in the most recent ACS estimates.

Ottawa is ranked the 136th most populous place in Illinois, out of 1,461 places. This ranking is based on the Census definition of a place, which includes incorporated places like cities, towns, and villages, as well as unincorporated census-designated places (CDPs). Ottawa was ranked the 132nd most populous place in the 2020 Census.

Ottawa's White Population

15,229 residents of Ottawa, or 82.6% of the population, identify as White. The share of White residents in Ottawa is significantly higher than in Illinois overall, where 58.1% of the population is White. Ottawa ranks 1060th statewide in terms of White residents as a share of the population, out of 1,461 places.

Since the 2020 Census, Ottawa's White population has declined by an estimated 2.4%. White residents' share of Ottawa's population has remained roughly unchanged at 82.6%.

Ottawa is more White than neighboring Naplate (81.8% White), and Wedron (0% White). Ottawa is less White than neighboring Dayton (98.5% White), Grand Ridge (92.1% White), and Marseilles (85.6% White).

Ottawa's Black Population

458 residents of Ottawa, or 2.5% of the population, identify as Black. The share of Black residents in Ottawa is considerably lower than in Illinois overall, where 13.3% of the population is Black. Ottawa ranks 345th statewide in terms of Black residents as a share of the population, out of 1,461 places.

Since the 2020 Census, Ottawa's Black population has grown by an estimated 7.0%. Black residents' share of Ottawa's population has remained roughly unchanged at 2.5%.

Ottawa is more Black than neighboring Dayton (0% Black), Naplate (0% Black), Wedron (0% Black), Grand Ridge (0% Black), and Marseilles (0% Black).

Ottawa's Asian Population

184 residents of Ottawa, or 1.0% of the population, identify as Asian. The share of Asian residents in Ottawa is slightly lower than in Illinois overall, where 5.9% of the population is Asian. Ottawa ranks 368th statewide in terms of Asian residents as a share of the population, out of 1,461 places.

Since the 2020 Census, Ottawa's Asian population has declined by an estimated 4.7%. Asian residents' share of Ottawa's population has remained roughly unchanged at 1.0%.

Ottawa is more Asian than neighboring Dayton (0% Asian), Naplate (0% Asian), Wedron (0% Asian), and Grand Ridge (0.3% Asian). Ottawa is less Asian than neighboring Marseilles (3.9% Asian).

Ottawa's Hispanic Population

1,861 residents of Ottawa, or 10.1% of the population, identify as Hispanic. The share of Hispanic residents in Ottawa is lower than in Illinois overall, where 18.8% of the population is Hispanic. Ottawa ranks 268th statewide in terms of Hispanic residents as a share of the population, out of 1,461 places.

Since the 2020 Census, Ottawa's Hispanic population has grown by an estimated 4.0%. Hispanic residents' share of Ottawa's population has increased from 9.5% to 10.1%.

Ottawa is more Hispanic than neighboring Dayton (1.1% Hispanic), Wedron (0% Hispanic), Grand Ridge (4.6% Hispanic), and Marseilles (5% Hispanic). Ottawa is less Hispanic than neighboring Naplate (11.7% Hispanic).

Ottawa's Native American/Other Population

1 residents of Ottawa, or 0.0% of the population, identify as American Indian/Alaska Native/Native Hawaiian/Pacific Islander/Other. The share of Native American/Other residents in Ottawa is comparable to the share in Illinois overall, where 0.5% of the population is Native American/Other. Ottawa ranks 542nd statewide in terms of Native American/Other residents as a share of the population, out of 1,461 places.

Since the 2020 Census, Ottawa's Native American/Other population has declined by an estimated 98.9%. Native American/Other residents' share of Ottawa's population has decreased from 0.5% to 0.0%.

Ottawa is less Native American/Other than neighboring Grand Ridge (0.7% Native American/Other), and Marseilles (0.7% Native American/Other).

Ottawa's Multiracial Population

714 residents of Ottawa, or 3.9% of the population, identify as Multiracial. The share of Multiracial residents in Ottawa is comparable to the share in Illinois overall, where 3.4% of the population is Multiracial. Ottawa ranks 570th statewide in terms of Multiracial residents as a share of the population, out of 1,461 places.

Since the 2020 Census, Ottawa's Multiracial population has declined by an estimated 2.3%. Multiracial residents' share of Ottawa's population has remained roughly unchanged at 3.9%.

Ottawa is more Multiracial than neighboring Dayton (0.4% Multiracial), Wedron (0% Multiracial), and Grand Ridge (2.2% Multiracial). Ottawa is less Multiracial than neighboring Naplate (6.5% Multiracial), and Marseilles (4.8% 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.