Cost sharing reductions (CSRs) are discounts that lower the out-of-pocket costs you pay when you actually use health care, including your deductible, copayments, and coinsurance. They’re available through the health insurance marketplace to people with lower incomes, but only if you enroll in a Silver plan. Unlike premium tax credits, which reduce your monthly bill, CSRs kick in when you visit a doctor, fill a prescription, or go to the hospital.
How CSRs Lower Your Costs
A standard Silver plan covers about 70% of average health care costs, leaving you responsible for the other 30% through deductibles, copays, and coinsurance. When you qualify for cost sharing reductions, your Silver plan gets upgraded to cover a larger share, and that changes three things in practical terms.
First, your deductible drops. That means your insurance starts paying its share of medical costs sooner in the year. Second, your copayments and coinsurance go down. If a standard Silver plan charges a $30 copay for a doctor visit, a CSR-enhanced version of that same plan might charge $20 or $15. Third, your out-of-pocket maximum decreases, which caps the total amount you’d spend in a worst-case scenario like a serious illness or accident.
The key detail: you don’t pay extra for these benefits. Your monthly premium stays the same as the standard Silver plan price. The insurance company absorbs the difference.
Why You Must Pick a Silver Plan
CSRs only work with Silver-tier marketplace plans. If you qualify for cost sharing reductions but choose a Bronze, Gold, or Platinum plan instead, you lose the benefit entirely. You can still use premium tax credits on any metal tier, but the extra savings from reduced cost sharing disappear unless you select Silver.
This is one of the most common enrollment mistakes. Someone eligible for both premium credits and CSRs might see a Bronze plan with a lower monthly premium and switch, not realizing they’re giving up hundreds or thousands of dollars in potential out-of-pocket savings over the course of a year.
Income Levels and CSR Tiers
Not everyone who qualifies gets the same level of savings. CSRs come in three tiers based on household income relative to the federal poverty level (FPL). The lower your income, the more generous the cost sharing reductions.
- Income up to 150% FPL: Your Silver plan is boosted to cover 94% of average costs instead of the standard 70%. This is the most generous tier, with very low deductibles and minimal copays.
- Income between 151% and 200% FPL: Coverage increases to 87% of average costs. You’ll still see significantly reduced deductibles and copays compared to a standard Silver plan.
- Income between 201% and 250% FPL: Coverage rises to 73% of average costs. The savings are more modest but still meaningful, particularly for the out-of-pocket maximum.
To put those income ranges in dollar terms using 2025 poverty guidelines: a single person qualifies for some level of CSR with an annual income between roughly $15,650 and $39,125. For a family of four, the range is $32,150 to $80,375. The exact tier you fall into within that range determines how much your cost sharing drops.
What the Savings Actually Look Like
The difference between a standard Silver plan and a CSR-enhanced one can be dramatic, especially at the 94% tier. Consider that a standard Silver plan might carry a deductible of $4,000 or more. At the 94% level, that same plan could have a deductible under $200. Copays for doctor visits and prescriptions shrink proportionally, and the annual out-of-pocket maximum can drop by thousands of dollars.
At the 73% tier, the changes are smaller. You might see your deductible reduced by a few hundred dollars and your out-of-pocket cap brought down modestly. Still, for someone who uses health care regularly or has a chronic condition, even incremental reductions add up over a plan year.
How to Get CSR Benefits
You don’t apply for cost sharing reductions separately. When you fill out your marketplace application at HealthCare.gov (or your state’s exchange), the system evaluates your household income and size. If you fall within the qualifying range, you’ll see CSR-eligible Silver plans flagged during the shopping process. The reduced cost sharing is built into the plan automatically once you enroll.
There’s no extra paperwork and no separate approval step. But you do need to actively choose a Silver plan to activate the benefit. The marketplace won’t prevent you from picking another tier; it simply won’t apply the CSR savings if you do.
Silver Loading and How It Affects Pricing
There’s a quirk in how CSRs are funded that’s worth understanding because it can work in your favor. The federal government stopped directly reimbursing insurers for CSR costs in 2017, but insurers are still legally required to offer the reduced cost sharing. To make up the shortfall, most states allowed insurers to add the cost of CSRs onto Silver plan premiums only. This practice is called “silver loading.”
Because premium tax credits are calculated based on the price of Silver plans, inflated Silver premiums mean larger tax credits for everyone. If you use those bigger credits to buy a Bronze or Gold plan instead, you can sometimes find plans with very low or even zero-dollar premiums. This is a strategy some marketplace shoppers use deliberately, though it only makes sense if you don’t also qualify for CSRs (since choosing a non-Silver plan means losing that benefit).
Special Rules for American Indians and Alaska Natives
Members of federally recognized tribes get an expanded version of cost sharing reductions. If your income falls between 100% and 300% of the federal poverty level, you can enroll in a “zero cost sharing” plan through the marketplace, meaning no deductibles, copays, or coinsurance at all. That income ceiling is higher than the 250% FPL cutoff for standard CSR eligibility.
Regardless of income, tribal members who receive care from an Indian health care provider pay no out-of-pocket costs. One important detail: if a tribal member enrolls in the same marketplace plan as a non-tribal household member, the extra savings won’t apply. Tribal and non-tribal members in the same household should enroll in separate plans to access the full benefit.