Rock Island County Population

1840–2026

142.15K

2026 projection

1.5% since 2020 (decrease)

050K100K150K200K1840186018801900192019401960198020002020

Source: U.S. Census Bureau decennial counts and annual estimates. 2026 is a projection. Values between recorded years are interpolated.

Use the left and right arrow keys to inspect population observations.

Population by year

Population estimates for Rock Island County. Annual change is shown as a percentage. Growth is the total change since the preceding observation.
2026142,147+2780.20%
2025141,869+2780.20%
2024141,591+6860.49%
2023140,905-670.05%
2022140,972-1,5131.06%
2021142,485-1,8721.30%
2020144,357+2,5821.82%
2019141,775-7470.52%
2018142,522-1,3020.91%
2017143,824-1,1530.80%

Showing 10 of 33 years.

Rock Island County Demographics

40.3median age

Median age

Female41.3 yrs
Male39 yrs

Adults

110,666
29,061 seniors (65+) · 26% of adults81,605 other adults

Sex

Female 50.5% · 72,135Male 49.5% · 70,622

Population by age

MaleFemale85+ years, male: 1,27285+ years, female: 2,15880–84 years, male: 1,65980–84 years, female: 1,98675–79 years, male: 2,18575–79 years, female: 2,94470–74 years, male: 4,12170–74 years, female: 4,06165–69 years, male: 3,76065–69 years, female: 4,91560–64 years, male: 4,79560–64 years, female: 4,82455–59 years, male: 4,10655–59 years, female: 4,32050–54 years, male: 4,12450–54 years, female: 4,07745–49 years, male: 4,09445–49 years, female: 3,95240–44 years, male: 4,55440–44 years, female: 3,96235–39 years, male: 4,39635–39 years, female: 4,59330–34 years, male: 4,39830–34 years, female: 4,27025–29 years, male: 4,21625–29 years, female: 4,29020–24 years, male: 4,53020–24 years, female: 4,31215–19 years, male: 4,93915–19 years, female: 4,49910–14 years, male: 4,59010–14 years, female: 4,7915–9 years, male: 4,7035–9 years, female: 4,1290–4 years, male: 4,1800–4 years, female: 4,05285+80–8475–7970–7465–6960–6455–5950–5445–4940–4435–3930–3425–2920–2415–1910–145–90–42K2K4K4K

Hover or tap an age group to see exact counts. Use the up and down arrow keys to inspect age groups.

U.S. Census Bureau, 2024 ACS 5-year estimates · Table S0101

Race and ethnicity

Tap a square or a group below to highlight it.

Each square is about 1% of residents (roughly 1,428 people).

Hispanic or Latino residents can be of any race. All other groups exclude Hispanic residents.

U.S. Census Bureau, 2024 ACS 5-year estimates · Table B03002

Rock Island County Income

$67,159median household income

Median household income

$67,159

Half of households earn more, half earn less

Median earnings

$47,164

Typical yearly pay for a worker 25 or older.

Poverty rate

15.5%

About 1 in 6 residents

U.S. Census Bureau, 2024 ACS 5-year estimates · Tables S1901, S1501, S1701

Rock Island County Marital Status

47% of residents age 15 and older are married.

MarriedNever married
Overall
Male
Female
Marital status of residents age 15 and older
StatusOverallMaleFemale
Married47%49%45%
Never married33%36%30%
Divorced12%10%13%
Widowed7%4%10%
Separated2%1%2%

U.S. Census Bureau, 2024 ACS 5-year estimates · Table S1201

Sources

8 sources, all from the U.S. Census Bureau

Population

American Community Survey, 2024 5-year