In January 2020, the proposed American Health Care Act would end the enhanced federal funding for new enrollment in the ACA’s Medicaid expansion. States could continue to receive the enhanced match for people enrolled as of that date, provided they don’t have a gap in coverage of more than one month. Drawing on data from the 2016 Commonwealth Fund Biennial Health Insurance Survey, the Commonwealth Fund’s Sara R. Collins and Munira Z. Gunja show that millions of people with Medicaid will likely lose their coverage if the House bill is enacted.