Illinois Policy has an analysis of population changes from mid-year 2023 to mid-year 2025.
“McHenry County was the second-largest gainer of domestic migrants in the state,” jumps out.
Here is the article:
While Illinois’ total population grew slightly last year, many areas of the state experienced population decline. People moved out of state from half the counties.
Of Illinois’ 102 counties, 64 saw their populations drop last year, according to estimates released March 13 by the U.S. Census Bureau.
While the statewide population grew by 67,899 residents from July 2023 to July 2024, thanks largely to a massive surge in international migration, most of the state’s counties shed population.
The largest population losses were in St. Clair, Vermillion and Madison counties. Alexander, Calhoun and Pulaski counties saw the fastest rates of population decline.
Of the counties that added population last year, Cook, DuPage, Will and Lake counties grew the most last year.
Kendall, Champaign and Ford counties grew at the fastest rates.
Generally speaking, population losses are affecting Illinois’ more rural areas. However, moves out of state are acting as a drag on both rural and urban area populations.
For example, while Cook, DuPage and Lake counties were among those whose population grew the most last year, these were the counties that suffered the largest exodus of residents leaving for other parts of the country, as their population increases were largely supported by a spike in international migration. Cass, Alexander and Champaign Counties experienced the fastest rate of domestic outmigration relative to the size of their population.
On the other end of the spectrum, Kendall County added the most residents via domestic migration, both in numeric terms and relative to the size of its population. This is likely from attracting residents from Chicago or other collar counties.
McHenry County was the second-largest gainer of domestic migrants in the state.
Comparing domestic migration across all 50 states, Illinois’ loss of 56,235 is only beaten by California, losing 239,575, and New York, losing 120,917.
Even when considering population size, Illinois ranks 46th in domestic migration with only Alaska, California, New York and Hawaii losing residents to other states at a faster rate.
Surveys of those who have left the state – where taxes are not a response option – showed the major reasons Illinoisans have chosen to leave have been for better housing and employment opportunities, both of which have been made worse by poor public policy in Illinois.
High taxes were the No. 1 reason why Illinoisans considered leaving the state. Polling from NPR Illinois and the University of Illinois found 61% of Illinoisans thought about moving out of state in 2019, and the No. 1 reason was taxes.
The Paul Simon Public Policy Institute found 47% of Illinoisans wanted to leave the state, and “taxes are the single biggest reason people want to leave” with 27% of respondents citing taxes as the motive for departing in 2016.
More recent polling conducted by Echelon Insights in 2023 substantiated those sentiments.
Unfortunately, there have been renewed proposals by state lawmakers to eliminate Illinois’ constitutionally protected flat income tax, which would likely only exacerbate the state’s tax burden. Senate Joint Resolution Constitutional Amendment 04, introduced Feb. 5 by state Sen. Robert Martwick, D-Chicago, and a similar constitutional amendment filed in the Illinois House, House Joint Resolution Constitutional Amendment 08, filed by state Rep. Curtis Tarver, D-Chicago, both seek replace Illinois’ flat income tax with progressive income tax structures.
When comparing states based on income tax structures, those with flat or no income tax attract the most residents, while those with progressive income taxes tend to push them away.
State lawmakers should pay attention to the common themes among states that are growing, or shrinking, because of domestic migration.
If state leaders refuse to acknowledge these realities and ignore why so many Illinoisans are leaving – taxes and business regulations that make life harder – the state can expect to see the continued exodus of residents to other states.
