Small Business Administration chief Karen Mills is leaving the agency. (Kevin Lamarque/Reuters)

More Cabinet vacancies are coming. Karen Mills, head of the Small Business Administration, is leaving the administration, the White House announced.

“Because of Karen’s hard work and dedication, our small businesses are better positioned to create jobs and our entire economy is stronger,” President Obama said in a statement.

Some though it likely that Mills, whose job President Obama elevated to Cabinet rank last year, would stay on in a second term. But now it seems there’s another job opening for the White House to fill.

And don’t look to Mills’s deputy, Marie Johns, to step up and fill her shoes. Johns sent colleagues an e-mail on Thursday informing them that she would be leaving the agency in May.

Mills’s business savvy — she led a private-equity firm and spent a career in the private sector — won her plaudits and made her an important face of the administration’s small-business efforts.