More than half of Illinois counties suffer outmigration

Residents are leaving every corner of Illinois for other states despite surging international migration propping up the total population.

People move out all over Illinois.

Eight of 11 metro areas in the state and more than half its counties saw net outmigration to other states in the year ending last July 1, according to Census Bureau estimates released Thursday.

Illinois lost more than 40,000 residents to other states in 2025, though the state’s population grew marginally because of nearly 45,000 international migrants coming in and roughly 11,000 more births than deaths.

Still, Illinois struggles to retain residents, ranking third-worst in the nation in residents leaving for other states.

The new data show that the Chicago-Naperville-Schaumburg metropolitan area lost the most residents to other areas, with more than 35,000 leaving last year. The next-largest loss was in Champaign-Urbana, where 2,118 residents moved away.

Despite the large outmigration, the continued surge in international migration paired with the natural increase in population — births minus deaths — meant these areas still saw slight increases in total population. The Illinois portion of the Davenport-Moline-Rock Island and Springfield metro areas also grew last year despite suffering domestic outmigration.

Areas that have seen lower levels of international migration and where there are more deaths than births are seeing population decline. Peoria, Decatur and Kankakee all experienced both domestic outmigration and population decline. While Bloomington saw more births than deaths, domestic outmigration of more than 1,000 residents led to overall population decline.

The Illinois portion of the St. Louis metro area gained residents from domestic migration, but not enough to offset the natural population decline, which resulted in a net decrease of 914 residents.

Rockford was the only metro area in the state to experience population growth because of increased domestic migration and international migration and more births than deaths.

The new estimates also reveal that the majority of counties across the state, 55 of 102, also saw outmigration last year. That was the primary reason why 64 counties experienced population decline, though some counties with positive domestic migration experienced population loss, as deaths frequently outpaced births in more rural areas.

Chicago-area counties experienced the largest domestic migration losses. Cook County lost 31,114 residents to other states; DuPage County lost 5,854, and Lake County lost 3,176.

McHenry and Kendall counties gained the most residents from domestic inmigration last year, adding 1,494 and 1,276, respectively.

Downstate counties are seeing the fastest rates of population decline from domestic outmigration. Cass, Edwards and Champaign counties each experienced more than 10 outmigrants per 1,000 residents last year, the fastest rates in the state.

However, Bond County, in the St. Louis metro area, gained nearly 24 domestic migrants per 1,000 residents last year, by far the fastest rate in the state. Montgomery and Piatt counties each added more than 10 domestic migrants per 1,000 residents last year.

Recent Census Bureau data shed light on one of the potential reasons so many Illinoisans are leaving the state: high taxes. In 2024, 95% of those who left Illinois fled to states with lower tax burdens.

That’s further evidence of what Illinoisans routinely tell pollsters: High taxes are the No. 1 reason residents consider leaving. Polling from NPR Illinois and the University of Illinois Springfield found that 61% of Illinoisans thought about moving out of the state in 2019, with taxes the No. 1 reason.

Back in 2016 the Paul Simon Public Policy Institute found that 47% of Illinoisans wanted to leave the state, and “taxes are the single biggest reason people want to leave,” with 27% of those respondents citing that as the motive . More recent polling by Echelon Insights in 2023 substantiated that sentiment.

Illinoisans face one of the highest state and local tax burdens in the nation, including the highest property taxes and seventh-highest sales taxes. In 2017 Illinois’ income tax endured the largest permanent rate hike in state history, when lawmakers hiked income taxes by 32% from 3.75% to 4.95%.

Despite Illinois’ continued outmigration amid an onslaught of high taxes, state lawmakers are again pushing for higher income taxes in the current legislative session, including the potential to tax retirees. Another year of residents fleeing for other states should be a wakeup call to the state’s leaders, who refuse to adopt policies that would make it more appealing for residents to stay in Illinois.

Easing Illinoisans’ tax burdens and reducing arduous business regulations are necessary to make the state more affordable and stop the departures. More tax hikes will mean fewer residents.