Kentucky is one of them. In 2017, lawmakers passed a bill stripping local municipalities of the power to require employers to provide paid time off for illness or injury.
Kameron Dawson, Southern office legal director for the advocacy organization A Better Balance, said it leaves many workers without an option to take sick days.
"That means that for Kentucky workers, especially if their employer does not have their own paid sick time policy, they are essentially unable to use any time off for things like a hospital stay or an illness or the flu," Dawson explained. "They're also unable to take time off for their family members who may be ill."
In the absence of federal laws guaranteeing paid sick leave for workers, some cities have passed their own, including Chicago, Minneapolis, Pittsburgh and Seattle. Supporters of such laws said paid leave mandates create financial hardship for businesses.
Nationwide, the report found about 27 million workers do not earn paid sick days. Many of them work low-wage and part-time jobs and they are disproportionately likely to be women, younger workers and people of color, according to the report. More than half the Black labor force, 56 %, lives in one of the 18 states prohibiting local paid sick time protections.
Dawson argued offering paid sick leave can be a draw for qualified workers in regions with workforce supply issues.
"It actually is a great recruitment and retention tool for employees and employers to retain essential workers," Dawson emphasized. "And it ensures that we're not spreading harmful illnesses in the workplace."
Kentucky also bars local governments from raising the minimum wage higher than $7.25 an hour, the same as the federal requirement.
This story is based on original reporting by Anna Claire Vollers for the Kentucky Lantern.