Rep. Tim Murphy (R-Pa.), chairman of the Oversight subcommittee, added that uncertainty about the law's effects has only grown over time.
"Members on this committee may have their own opinions on whether passage of the Affordable Care Act was the right decision, but we cannot disagree on the facts," Murphy said.
"The costs and requirements of this law are forcing many businesses across the country to make difficult decisions."
President Obama's signature healthcare law has many provisions related to business, including a requirement that many employers offer healthcare coverage to their workers.
Republicans have long opposed this rule, saying many businesses cannot afford to provide health insurance without significantly limiting their growth.
This week marks the one-year anniversary of the Supreme Court's decision to uphold the law.
Partisan bickering is as strong as ever as the Obama administration prepares for full implementation on Jan. 1.
Wednesday's hearing was held by Murphy's subcommittee on Oversight and Investigations.