Project 2025, the right-wing policy blueprint spearheaded by the Heritage Foundation and co-authored by more than 100 former Trump administration staffers, has been denounced for several of its tax proposals, including slashing the corporate tax rate and the capital gains tax to benefit wealthy Americans—but a research group on Wednesday warned that one economic policy that hasn’t gotten much attention could “greatly increase” financial hardships for millions of working families.

EPI Action, a nonpartisan research and advocacy organization affiliated with the Economic Policy Institute, published an analysis of a proposal that appears on page 7 of Project 2025’s section on the Treasury Department—whose authors include at least two people who served on Republican presidential nominee Donald Trump’s campaign and transition team for his term in office.

The proposal calls to tax employers on workplace benefits that exceed $12,000 per worker annually—which would undoubtedly “lead to employers cutting back on these benefits,” wrote Josh Bivens, chief economist for EPI Action.

Based on health insurance benefits that are provided to more than 150 million Americans through their employers, Bivens found, more than 15 million workers would see their benefits taxed under the Project 2025 plan.

Those workers would collectively pay over $12 billion more in taxes if their employers shifted away from providing benefits as a cost-cutting measure.