Cost Sharing Reductions (CSRs) are a discount on what an enrollee pays when using care: lower deductibles, copayments and coinsurance, and a lower out-of-pocket maximum. They do not lower the monthly premium; that is the premium tax credit's job.
Who qualifies: the CDI outline says consumers qualify for varying CSRs between 138% and 250% of FPL. Under federal rules, expected household income may not exceed 250% of FPL. The 138% floor reflects that most adults below 138% go to Medi-Cal instead.
Silver only, through the Exchange: CSRs go only to an enrollee in a Silver plan bought through the Exchange. A Silver plan bought outside the Exchange, or a Gold or Bronze plan, gets no CSRs, although the APTC can still be used with any metal tier.
How much: a standard Silver plan pays about 70% of covered costs. With CSRs, the plan's share rises to:
94% at 100% to 150% of FPL
87% above 150% up to 200%
73% above 200% up to 250%