Under the rule, employees earning up to $55,068 a year would be eligible to earn the overtime rate — time-and-a-half pay — for hours worked beyond a standard full-time schedule of 40 hours a week. The threshold would adjust every three years to take inflation into account. Currently, only salaried workers making $35,568 or less are eligible for overtime.

Labor advocates have long supported expanding overtime eligibility, and while they applauded the Labor Department’s proposal, some said it didn’t go far enough. But many Connecticut businesses say the change could hurt their bottom line — particularly in a state where operating a business can be more expensive than in other states.

“Connecticut has one of the highest rates of income and wage inequality in the United States, which is a highly inequitable country,” said Lauren Ruth, a researcher with economic policy and child advocacy group Connecticut Voices for Children. The new rule, Ruth said, “would boost the wages of some of our lower and middle income workers and help to narrow that income and wage gap.”

Using state labor data, Ruth estimated that at least 389,000 and likely up to 600,000 salaried workers in Connecticut could become eligible for overtime pay under the new rule. The cohort could include workers in manager-level positions in sectors like manufacturing, property management, social services, early education and food service.

Eric Gjede, vice president for public policy with the Connecticut Business and Industry Association, said, “Employers in Connecticut are already struggling right now with the cost of doing business.” With high health care and energy costs to contend with, Gjede said, businesses were disappointed that the General Assembly didn’t do more to reduce their tax burden during this year’s legislative session.