Study author Brian Haile wrote that the Patient Protection and Affordable Care Act limits access to the premium assistance tax credit programs to eligible individuals earning between 100 percent and 400 percent of the federal poverty level. The assumption was that those under 138 percent of FPL would be eligible for the Medicaid expansion.

However, last summer’s U.S. Supreme Court ruling made optional for states, and consequently in states that do not expand Medicaid, those in the 100- to 138-percent range will not be eligible for Medicaid. But they will qualify for premium tax assistance.

Employees enrolling in Medicaid generally will not trigger any employer penalty, Haile wrote, but getting the tax assistance could. Under the “shared responsibility” provisions of PPACA, employers that offer health coverage and have 50 or more full-time equivalent employees must generally pay up to $3,000 penalties for each employee who qualifies for and enrolls in the premium assistance tax credits.