Illinois saw its population grow by 16,108 residents between July 2024 and June 2025, according to new U.S. Census Bureau estimates. This marks the third consecutive year of gains, thanks almost entirely to a surge in international migration since 2022. Without this influx, Illinois would have continued to lose residents, as over 40,000 people moved to other states last year. Natural growth—more births than deaths—added just 11,000 people.
Chicago remains the main destination for international newcomers, fueling political debate over state and city resources. At the same time, Illinois continues to rank near the top nationwide for domestic outmigration, trailing only California and New York in the number of residents lost to other states.
Census data reveal high taxes as the leading reason for the exodus; in 2024, 95% of those leaving Illinois moved to states with lower tax burdens. Illinois faces some of the nation’s highest property and sales taxes, and enacted its largest income tax hike in 2017.
Despite persistent outmigration and warnings about the state’s tax climate, lawmakers are again considering additional income tax increases, including the possibility of taxing retirement income. While international migration has kept Illinois’ population in positive territory, the trend raises questions about the state’s long-term growth and sustainability.