President Barack Obama and US Labor Secretary Thomas E. Perez in 2013. (Associated Press)

The Obama administration has unveiled its new overtime rule, which will make more than four million workers eligible for extra pay. The rule would have big implications for employees at colleges and universities, and college presidents worry it carries unintended consequences.

Under the new rule, the salary limit for workers to qualify for overtime would increase from about $23,660 to $47,476. Professors and teachers would be exempt, but many post-docs and research assistants who don't teach would be eligible for overtime.

"When this new rule goes into effect on December 1, that's going to be a driver of human resource costs," said Steven Bloom, director of government relations at the American Council on Education.

Bloom says requiring such a "costly change" to be implemented so quickly will force many college presidents to seek alternative revenue.

"One of the biggest ways to do it, unfortunately, are increased tuitions," he said.

The American Council on Education says cash-strapped colleges may also have to cut services and possibly make layoffs.

"We are disappointed that the department failed to address so many of the concerns raised by the entire higher education community," ACE president Molly Corbett Broad said in a statement. "We will work to help our institutions understand the costs… of implementing these changes, even as we continue to press for improvements to the new rules."

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