Part-time workers eligible for healthcare benefits at large companies in the United States elect coverage at a significantly lower rate than full-time employees, according to the ADP 2012 Study of Large Employer Health Benefits released today by the ADP Research Institute.

The study found 88 percent of the full-time workforce is eligible for benefits and 77 percent actually selected health coverage, resulting in 68 percent of the total full-time workforce being covered by their employer’s health plan.

By contrast, the part-time workforce makes up 23 percent of the total workforce and only 15 percent of these part-time employees are eligible for benefits, with 53 percent choosing to participate. The result is that 8 percent of the part-time workforce participates in their employer’s health coverage.

The average employer within the study contributed $7,225 per annum in health premiums for each employee who enrolled in the employer’s group health plans for benefit year 2012.

The Affordable Care Act, which defines full-time employees as those credited with service equal to at least 30 hours per week or 130 hours per month, may have an impact on the number of employees who may qualify for coverage.

This study is based on 2012 non-union employee level data from a subset of ADP’s health and welfare benefits clients of approximately 300 U.S.-based organizations. Each of the companies in the study employs 1,000 or more employees, including both full-time and part-time workers.