What are ACA cost-sharing reductions (CSRs), who qualifies for them, and how must you enroll to receive them?

Cost-sharing reductions are additional subsidies that reduce the deductibles, co-pays, and out-of-pocket maximums on ACA marketplace plans. They are available to households with incomes between 100 and 250% of the federal poverty level. The critical enrollment rule is that CSRs are only available when you select a Silver-tier plan — enrolling in a Bronze, Gold, or Platinum plan makes you ineligible for CSRs even if you qualify by income. Since 2017, the federal government has stopped reimbursing insurers for CSR costs, so insurers embed the cost into Silver plan premiums, which has made Gold plans unusually competitive in many markets.