At some point between now and the beginning of July, 2015, the Supreme Court will decide King v. Burwell. If the Court sides with the plaintiffs and invalidates the Internal Revenue Service (IRS) rule permitting federally facilitated exchanges to grant premium tax credits, the effects will be dramatic. Premium tax credits and cost-sharing reduction payments in the federally facilitated exchanges would probably cease at the end of July.

At that point, approximately 8 million Federally Facilitated Marketplace (FFM) enrollees currently receiving subsidies would have to decide whether to continue to pay the premiums themselves. Without the subsidies, their premiums would increase 122 to 774 percent depending on the state, with a national average increase of 255 percent. Millions of individuals would likely be unable to afford these premium increases and would cease paying their premiums. Their coverage would probably end 30 days thereafter.