This history appeared for the first time KFF Health News.
With Donald Trump returning to the White House and Republicans taking full control of Congress in 2025, Medicaid expansion under the Affordable Care Act once again faces necessity.
More than 3 million adults in nine states would be at immediate risk of losing health insurance if the Republican Party cut additional federal Medicaid funding that allowed states to expand eligibility, according to KFFa nonprofit health information organization that includes KFF Health News and Georgetown University Center for Children and Family. That’s because states have introduced trigger laws that will quickly end Medicaid expansion if federal funding declines.
The states are Arizona, Arkansas, Illinois, Indiana, Montana, New Hampshire, North Carolina, Utah and Virginia.
!function(){“use strict”;window.addEventListener(“message”,(function(a){if(void 0!==a.data[“datawrapper-height”]){var e=document.querySelectorAll(“iframe”);for(var tw a.data[“datawrapper-height”])for(var r=0;r[r].contentWindow===a.source){var i=a.data[“datawrapper-height”][t]+”px”;i.e[r].style.height=i}}}))}();
The 2010 Affordable Care Act encouraged states to expand their Medicaid programs to cover more low-income Americans who did not have health insurance through their jobs. Forty states and the District of Columbia agreed, expanding health insurance coverage to about 21 million people since 2014 and helping lower the U.S. uninsured rate to a record low.
In return, the federal government covers 90% of the costs of covering the increased population. That’s significantly higher than the federal figure for other Medicaid beneficiaries, which averages about 57% nationwide.
Conservative political groups, which generally oppose the ACA, say the program costs too much and covers too many people. Democrats say expanding Medicaid has saved lives and helped communities by extending coverage to people who couldn’t afford private insurance.
If Congress cuts federal funding, Medicaid expansion would be at risk in all states that opted for it – even those without trigger laws – because state legislatures would be forced to make up the difference, said Renuka Tipirneni, an associate professor at the U.S. Michigan School of Public Health.
Decisions to maintain or withdraw expansion “would depend on state-level policy,” Tipirneni said.
For example, Michigan approved a trigger for its Medicaid expansion in 2013, when it was controlled by a Republican governor and legislature. Last year, when the government was controlled by Democrats, the state eliminated the mechanism that triggered funding.
Six of the nine states with such laws – Arizona, Arkansas, Indiana, Montana, North Carolina and Utah – voted for Trump in the 2024 election.
Most of the nine states trigger actions if federal funding falls below the 90% threshold. Arizona’s trigger mechanism would eliminate its expansion if funding falls below 80%.
Montana law phases out expansion below 90% funding but allows it to continue if lawmakers identify additional funding. Under state law, Montana lawmakers must reauthorize Medicaid expansion in 2025, otherwise the expansion will end.
Researchers at KFF and the Georgetown Center estimate that in states with triggers, between 3.1 and 3.7 million people would quickly lose coverage. The difference depends on how states treat people who were added to Medicaid before the ACA expansion; may still be eligible even if the expansion ends.
Three other states – Iowa, Idaho and New Mexico – have laws that require their governments to mitigate the financial impact of losing federal Medicaid expansion funds but that do not automatically end the expansion. After including these three states, about 4.3 million people enrolled in the Medicaid expansion would be at risk of losing coverage, according to KFF.
The ACA authorized the expansion of Medicaid to adults with incomes up to 138% of the federal poverty level, or about $20,783 per person in 2024.
Nearly a quarter of the 81 million Medicaid enrollees nationwide are participating in the program because of its expansion.
“As the expansion matching factor decreases, it is likely that all states will need to evaluate whether to continue the expansion because it would require a significant increase in state spending,” said Robin Rudowitz, vice president and director of the Medicaid and Uninsured Persons Program at KFF. “If states drop coverage, there will likely be an increase in the number of uninsured people, which will reduce access to care in red and blue states that have adopted the expansion.”
States rarely limit eligibility for social programs such as Medicaid once they are granted.
These factors make it politically easier for state lawmakers to end Medicaid expansion because they would not have to take any modern actions to reduce coverage, said Edwin Park, a research professor at Georgetown University’s Center for Children and Families.
To see the impact of trigger laws, consider what happened after the Supreme Court overturned Roe v. Wade in 2022, and with it the constitutional right to abortion. Conservative lawmakers in 13 states have drafted trigger laws that would automatically implement bans if the state’s abortion rights were stripped away. These state laws caused the restrictions to go into effect immediately or shortly after the court’s ruling.
States have adopted trigger mechanisms in Medicaid expansion to persuade lawmakers skeptical of putting state dollars on the hook for a federal program unpopular with most Republicans.
It’s unclear what Trump and congressional Republicans will do with Medicaid once he takes office in January, but one indicator could be a recent recommendation from the Paragon Health Institute, a leading conservative policy organization headed by former Trump health adviser Brian Blase .
Paragon proposed that starting in 2026, the federal government phases out 90% of the federal match for expansion until 2034, when it will reach each state’s federal match for established enrollees. Under this plan, states can continue to receive ACA Medicaid expansion funds but limit coverage to enrollees with incomes up to the federal poverty level. Currently, to receive development funds, countries must provide everyone with insurance up to 138% of the poverty level.
Daniel Derksen, director of the Center for Rural Health at the University of Arizona, said it’s unlikely Arizona will eliminate the cause and make up for lost federal funding. “It would be difficult to sell now because it would be a big burden on the budget,” he said.
Medicaid has been in the crosshairs of Republicans in Washington before. Republican congressional leaders in 2017 proposed legislation to cut federal expansion funding, which would shift billions in costs to states. This plan, part of the Obamacare repeal strategy, ultimately failed.
KFF Health News is a nationwide newsroom dealing with broadly understood journalism on health issues and is one of the main operational programs of KFF – an independent source of research, surveys and journalism in the field of health policy. Find out more about KFF.
YOU MAKE OUR WORK POSSIBLE.