Cost-sharing reductions (CSR) that lower deductibles, copayments, and coinsurance for Marketplace enrollees are available to households with incomes between:

Why A is correct

The ACA provides cost-sharing reductions to eligible Marketplace enrollees whose household income is between 138% and 250% of the federal poverty level. These enrollees receive enhanced plan benefits with lower deductibles, copayments, and coinsurance, and the reductions are available only on Silver-tier plans sold through the Exchange. The 138% to 250% FPL band is the defined CSR eligibility range, distinct from the higher APTC band, so A correctly identifies the income window for cost-sharing reductions. The CSR program is specifically designed to make Silver plan coverage more affordable for lower-income enrollees who are above the Medi-Cal threshold but still struggle with out-of-pocket costs.

Why the other options are wrong

• B) Households in the 250% to 400% FPL range may receive premium tax credits but are above the CSR threshold and therefore receive no cost-sharing reductions. Those households may qualify for premium tax credits but are above the CSR income band.
• C) Households below 138% FPL qualify for Medi-Cal rather than Marketplace cost-sharing reductions; there is no CSR eligibility band starting at 50% FPL. No CSR tier exists below 138% FPL, where Medi-Cal coverage takes over.
• D) Households above 400% FPL receive neither premium tax credits nor cost-sharing reductions under the standard ACA rules, so 400% to 600% FPL is not a CSR band. Households above 400% FPL receive neither CSR nor premium assistance under the standard rules.

Memory hook

CSR lives between 138 and 250. Below is Medi-Cal, above 250 the Silver discounts disappear.

Why A is correct

Cost-sharing reductions (CSR) lower the deductibles, copays, and coinsurance that a marketplace enrollee pays, and they apply only to enrollees who select a Silver-tier plan. CSR is available to eligible households with income between 138% and 250% of the federal poverty level. Below 138% FPL, most adults qualify for Medi-Cal instead, and above 250% FPL the CSR subsidy phases out. The 138-250% band is a core PPACA number tested on the A&H exam. CSR applies only to Silver-tier plans because the reduction is built into the plan's cost-sharing design, and the federal government compensates the insurer for the lowered member cost shares.

Why the other options are wrong

• B) Income at or below 100% FPL routes most adults to Medi-Cal rather than to marketplace coverage with CSR.
• C) The 400-500% FPL range is far above the CSR ceiling; enrollees above 250% FPL receive no cost-sharing reductions.
• D) The 300-400% FPL range exceeds the CSR threshold; in that band only premium subsidies, not CSR, may apply.

Memory hook

CSR lives in the 138-250% band — the sweet spot where help with deductibles and copays kicks in.