As of April 2015, 21 states have chosen not to expand Medicaid eligibility under the Affordable Care Act. All but one of those states have also chosen to rely on federally facilitated marketplaces. If the Supreme Court finds for the plaintiff in King v. Burwell, the combined effect of not expanding Medicaid and losing federal support for marketplace coverage for the low-income population would be dramatic for the 20 states affected by both decisions. In total, 9.8 million people would be uninsured who would have otherwise been insured. Assuming that marketplace financial assistance is not replaced and assuming those states do not choose to expand Medicaid, the total loss in federal spending from 2016 to 2025 would be $721 billion.

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