The divide between so-called "right-to-work" states and those with stronger labor protections was stark in 2024, with the former shedding an estimated 179,000 union members over the course of the year, and the latter adding 9,000.

According to an analysis from the Illinois Economic Policy Institute and the University of Illinois, workers in right-to-work states — defined as those with laws barring union contracts from requiring members to pay dues — earned 7% less on average than their counterparts in union-friendly states. Dating back to 2019, wages in right-to-work states have also grown 1.3% slower compared to collective bargaining states. 

Union membership in the U.S. has gradually fallen for decades, dropping from one in every four workers in 1973, to one in 10 today. The study attributes recent losses to an increase in states that passed right-to-work laws following 2018's Janus v. AFSCME Supreme Court decision, where justices ruled that requiring union members to pay dues represents a violation of the First Amendment's free speech guarantee. Unions have since criticized the decision for limiting their ability to organize new members, advocate for employees, and challenge union busting efforts in court.

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After Michigan repealed its right-to-work law in early 2024, the state gained 15,000 union members by the year's end, after losing nearly 70,000 union members in the 11 years the law had been in effect. In Illinois — which codified collective bargaining rights in its state constitution in 2022 — union members earn 12% higher wages on average, are 8% more likely to be homeowners, 5% more likely to have health insurance, and were significantly less likely to rely on Medicaid, food stamps, and other forms of government assistance.

"We encourage policy makers to reflect on the data in this report, and to reconsider their support for ‘right-to-work’ laws and other policies that have weakened unions," the study's co-authors Dr. Robert Bruno and Frank Manzo said. "The data conclusively shows these measures have only proven to depress wages for working families already struggling with rising costs, and to create additional welfare dependence paid for by taxpayers."