Large employer-sponsored health plans are generally subject to fewer federal insurance requirements than small group plans and coverage purchased by individuals and families on their own. They are generally not required to provide “essential health benefits,” such as emergency services, maternity and newborn care, mental health coverage and substance abuse treatment, although many do.

A decision by Obama appointees in 2011 discouraged the use of association health plans as a substitute for Affordable Care Act policies because officials feared they would be used to circumvent the law’s coverage mandates. The Obama administration said that coverage offered to dozens or hundreds of small businesses through a trade or professional association would not be treated as a single large employer health plan for the purpose of insurance regulation.

Instead, the Obama administration said, the government would look at the size of each business participating in the association, so that many small employers would still be subject to stringent federal rules.

The Trump administration, by contrast, wants to make it easier for small businesses to buy less expensive plans that do not comply with some requirements of the 2010 law.

Several states considered bills to treat health plans offered to small employers through a trade association as large-group coverage, exempt from federal rules that apply to small businesses. But the Obama administration blocked those efforts, saying they were pre-empted by the Affordable Care Act. Trump administration officials are reconsidering that interpretation, in view of the president’s vow to increase access to less expensive insurance.

Large-group plans are still subject to some requirements of the Affordable Care Act. They generally must cover children up to age 26 on their parents’ plans, cannot impose lifetime limits on covered benefits and cannot charge co-payments for preventive services like mammograms and colonoscopies.

But they are generally exempt from the requirements to provide a specified package of benefits and to cover a certain percentage of the cost of covered services.