SOUTH PORTLAND — Small business owners and self-employed workers at a roundtable discussion on Monday told Maine Gov. Janet Mills and U.S. Rep. Chellie Pingree that their health insurance premiums will spiral and cost thousands of dollars per month if certain Affordable Care Act tax credits expire.

“Out-of-pocket expenses for our family for health insurance next year will be upwards of $42,000,” said Ossian Riday, 54, a self-employed software developer from Topsham. “That is basically the equivalent of buying a new car every single year.”

Riday, speaking during the event held at Greater Portland Health in South Portland, said small business owners “need solutions for health care coverage without fear of financial disaster.”

The extension of some of the subsidies — called Enhanced Premium Tax Credits — was at the center of a debate that spurred this fall’s government shutdown, which ended on Nov. 12 without an agreement to extend the subsidies. The subsidies will expire Dec. 31 without an extension.

Another set of subsidies that helps reduce premiums for enrollees, the Advanced Premium Tax Credits, were part of the original ACA law and have no expiration date.

The enhanced subsidies were included in the coronavirus relief package first approved by Congress in 2021 and then extended a year later through 2025. During that time, ACA enrollment has soared nationally, going from 11.2 million in 2021 to more than 23 million this year, according to federal data.

The enhanced subsidies were designed to reduce premiums for most enrollees, but among those hardest hit if they go away are households earning more than 400% of the federal poverty level, or $84,600 for a family of two. Households in that income bracket would lose their tax credits if they expire, leaving many to face thousands per month in premium costs.

New Gloucester resident Penny Collins, who along with her husband owns a small engineering firm, said they would lose their tax credits, causing their health insurance premiums to skyrocket from about $15,000 per year to $33,000 per year for an equivalent plan.

“It’s very upsetting,” Collins said during the event Monday. “Our health insurance next year would cost more than our mortgage, car payment and utility bills combined.”

In Maine, the average premium would increase 77% if the enhanced tax credits end, according to the Maine Health Insurance Marketplace. The Urban Institute, a national think tank, projects 8,000 Maine residents would go uninsured in 2026 rather than pay the higher premiums. About 65,000 Maine residents are enrolled in an ACA plan this year, according to state statistics.

Hilary Schneider, director of Maine’s Health Insurance Marketplace, said 2,000 people have already canceled their ACA plans for 2026.

“Many people are worried and scared,” Schneider said during the event Monday. “We are being inundated with calls.”

Democrats and some Republicans are in favor of an extension of the enhanced credits, but so far the Trump administration and Republican leadership in Congress have been opposed. According to national news reports on Monday, President Donald Trump may propose a two-year extension of the subsidies, with a new cap on eligibility at 700% of the federal poverty level, or $148,050 for a two-person household. Trump was getting resistance to the plan from congressional Republicans on Monday, and an announcement was delayed, according to news reports.

The current enhanced subsidies have no cap, but prevent most from prohibitively expensive premiums by limiting premium costs to no more than 8.5% of household income.

Mills, who is campaigning in the 2026 Democratic primary for a chance to run against Sen. Susan Collins, R-Maine, said Trump and most Republicans have been hostile to the ACA since it was proposed. Mills said ideas floated by Republicans to replace or reform the ACA have not materialized.

“Where is that (plan)?” Mills said. “We’ve yet to see anything.”

Collins has said that she’s in favor of extending the ACA subsidies, as have the rest of Maine’s congressional delegation, including Rep. Jared Golden, D-2nd District, and Sen. Angus King, an independent who caucuses with Democrats.

Pingree, D-1st District, said Democrats are willing to negotiate with the Trump administration and congressional Republicans, but time is running short because people are already shopping for plans. Enrollees have to select a plan by Dec. 15 to have coverage starting Jan. 1. Open enrollment goes through Jan. 15 for plans that would begin on Feb. 1.

“For small business owners, there isn’t somewhere else to turn,” Pingree said. “This will have a detrimental impact on the Maine economy.”

Bethany Allen, of Bowdoinham, owner of Harvest Tide Organics farm, said she’s not yet sure how much her family’s premium will increase if the credits end. But she said the stability of the ACA has helped her business, and that the unknown caused by the credits ending would hurt their farm.

“The ACA has allowed us to recruit, hire and retain employees,” Allen said during the event. “It’s provided the equity and consistency that we need. It’s allowed us to grow our business.”

To shop on Maine’s ACA marketplace, go to www.coverme.gov.