WASHINGTON — President Obama will sign an executive order on Labor Day providing paid sick leave to 300,000 employees of federal contractors.

“Hardworking people should not have to choose between taking care of themselves or a loved one . . . and a day’s pay,” Obama adviser Valerie Jarrett told reporters Sunday on a conference call in advance of the Monday action.

Some contractors already provide sick leave, so the order would extend the benefit of up to seven paid sick days per year to an additional 300,000 workers, according to Washington estimates.

The administration said there would be no cost to the federal government and that the companies would actually gain from the requirement through reduced attrition and a healthier workforce.

“The cost of implementing this rule is offset by the efficiencies that come with reduced attrition, increased loyalty — all of those things that have been documented in a number of studies,” Labor Secretary Tom Perez told reporters.

Obama also will call on Congress to pass legislation expanding paid leave for all working Americans and to require paid maternity leave.

When the administration leaked the idea of the contractor requirement early last month, a US Chamber of Commerce official blasted it as executive overreach. Obama had called for legislation for paid sick leave for federal contractors’ workers in his State of the Union address.