Illinois on track to lose another congressional seat

Illinois is on pace to lose a seat in Congress based on new census data. International immigration and interstate migration are driving those projections.

Despite three straight years of population growth, Illinois lost nearly 445,000 people since 2020. That puts it on track to lose a congressional seat in 2030 when new maps are drawn.

The COVID-19 pandemic created a backlog of visa applications from 2021 to 2023. That period under former President Joe Biden had international immigration increases offset fewer births and more deaths among aging Baby Boomers, according to the Brennan Center.

The trend slowed starting in 2024. The second Trump term has “pursued much more restrictive immigration policies, the contours of which are still evolving,” as people being admitted for humanitarian reasons has been reduced and deportation efforts have increased.

The Trump administration’s immigration policies are likely to curb future growth in the international migration Illinois has been reliant on to see population growth. If more Illinois residents continue to leave to other states, the state’s population could switch to shrinking.

Illinois’ influx of immigrants, particularly in Chicago has been the center of heated political debate. The latest Census Bureau estimates confirm the extent of international migration to the state during the past several years, while raising questions of the sustainability of this trend.

Between 2024 and 2025, Illinois’ population grew by 16,108 residents, while Illinois’ loss of over 40,000 residents was only beaten by California and New York.

Meanwhile, the states that saw the most population growth since 2020 have been Florida and Texas.

In 2024, 95% of those leaving the state fled to states with lower tax burdens. As Illinoisans face one of the highest state and local tax burdens in the nation, including the highest property taxes and 7th highest sales taxes in the country. Illinois’ income tax endured the largest permanent rate hike in state history in 2017. State leaders currently in session are again pushing for higher income taxes, including the potential to tax retirees.

In 2030, a new centennial census will collect the state’s population formally. The trends of declining international migration and Illinois’ chronic outmigration troubles may lead to a loss in population in 2030, which would lead to fewer congressional seats and a potential reduction in Illinoisans’ voting power.