Insurers participating in the Affordable Care Act’s marketplaces are reassessing their participation and considering premium increases because of uncertainty over the law’s future. Through a series of interviews with 13 insurers participating in the marketplaces in 28 states, researchers explored how companies would respond to different repeal scenarios. They find that repeal of the individual mandate and a “repeal and delay” strategy without a concurrent replacement would lead insurers to exit the market or raise premiums. If payments for cost-sharing reductions cease, insurers would face significant financial losses; many would need to leave the market as soon as legally feasible.