The Trump administration announced a new federal rule Monday intended to expand worker access to 401(k) retirement plans. The rule explicitly approves Association Retirement Plans, expanding and simplifying the ways small businesses and other groups can band together to offer the plans. The administration estimates that as many as 38 million people could potentially become eligible due to the change, provided their employers choose to participate.

"Many small businesses would like to offer retirement benefits to their employees, but are discouraged by the cost and complexity of running their own plans," acting Labor Secretary Patrick Pizzella said. "Association Retirement Plans offer valuable retirement security to small businesses' employees through their retirement years."

The change says that professional associations or groups of employers can count as employers for the purposes of the Employees Retirement Income Security Act, something that allows them to create the retirement plans. In effect, it allows the creation of multi-employer pension plans, but using 401ks as the vehicle. Traditional multi-employer pension plans can become endangered, and the House recently passed legislation to create a loan program for troubled plans. A 401(k)-based system would circumvent that by letting workers hold on to an individual plan.

A senior Labor Department official said that the change, based on an executive order issued by President Trump last year, is aimed at making it possible for companies that have fewer than 100 employees to offer retirement plans by working with other employers or other entities. Most of those employers currently don't offer plans, the common explanation being they cannot afford to do it on their own. "We saw it as a big vacuum. No one had stepped up to ERISA and said you could expand it," the official said.