Medicare Part D costs break into three pieces: a monthly premium, an annual deductible, and copayments when you fill prescriptions

Your total Part D cost depends on which plan you choose, which drugs you take, and how much you earn. There is no single price — each insurance company sets its own premium and cost-sharing structure. The average monthly premium across all plans is around $34, but plans range from roughly $6 to $100+ per month. Your actual bill will be lower or higher depending on the specific plan and your income.

Most plans also have an annual deductible — the amount you pay out of pocket before the plan starts to help. In 2024, deductibles can be as low as $0 or as high as $545, depending on the plan you pick. After you meet the deductible, you typically pay a copayment (a set dollar amount) or coinsurance (a percentage of the drug cost) each time you fill a prescription.

Key Takeaways

  • Monthly premiums for Part D plans in 2024 average around $34 but vary widely by plan and location, ranging from about $6 to over $100.
  • Annual deductibles can range from $0 to $545 in 2024, and you choose the plan with the deductible that fits your budget.
  • You pay copayments or coinsurance for each prescription after you meet your deductible, with amounts varying by drug tier and plan.
  • If your income is below certain thresholds, you may receive subsidies that lower your premium, deductible, and copayments significantly.
  • Your costs can change each year because premiums, deductibles, and drug formularies (the list of covered drugs) are updated annually.

How premiums work and what affects yours

Your monthly premium is what you pay to the insurance company to keep your coverage active. In 2024, the national average is approximately $34 per month, but this varies by plan, by insurance company, and by where you live. Some plans in your area may cost $6 per month; others may cost $80 or more. The only way to know what is available to you is to check the plans offered in your ZIP code during the annual enrollment period (October 15 to December 7 each year).

If you have higher income, you may also pay an Income-Related Monthly Adjustment Amount (IRMAA). This is an extra charge added to your premium if your modified adjusted gross income exceeds certain thresholds. In 2024, the thresholds start at $97,000 for single filers and $194,000 for married couples filing jointly. The extra amount can range from $12 to $76.20 per month, depending on your income level. You will receive a notice from Social Security if IRMAA applies to you.

Deductibles and what you pay before coverage kicks in

Most Part D plans have an annual deductible. In 2024, deductibles range from $0 to $545. Some plans have no deductible at all — you start paying copayments right away. Other plans require you to pay the full cost of your drugs until you reach the deductible amount, then the plan begins to share costs with you.

The deductible resets every January 1. If you reach your deductible in November, you start over in January. Plans with higher deductibles often have lower monthly premiums, and plans with lower or no deductibles often have higher premiums. When you are comparing plans, add up the premium you will pay over the year, plus the deductible, plus what you expect to pay in copayments for your regular medications. That total is closer to your real cost than the premium alone.

Copayments and coinsurance for prescriptions

After you meet your deductible, you pay a copayment or coinsurance each time you fill a prescription. A copayment is a flat dollar amount — for example, $5 for a generic drug, $25 for a brand-name drug, or $50 for a specialty drug. Coinsurance is a percentage of the drug cost — for example, 25% of the price. Different plans use different structures, and the same drug may have different costs in different plans.

Part D plans organize drugs into tiers. Tier 1 is usually generic drugs with the lowest copayment. Tier 2 is preferred brand-name drugs. Tier 3 is non-preferred brand-name drugs. Tier 4 and 5 are specialty drugs and may have the highest copayments or coinsurance. Your plan's formulary (the list of covered drugs and their tiers) is available on the insurance company's website. If your doctor prescribes a drug that is not on the formulary or is in a high tier, you can ask the plan for an exception or ask your doctor about a different drug in a lower tier.

The coverage gap and catastrophic coverage

Part D has a coverage gap, sometimes called the "donut hole." Once you and your plan have spent a combined $5,030 on covered drugs in 2024, you enter the gap. In the gap, you pay a higher percentage of the drug cost — typically 25% of the price of brand-name drugs and generic drugs — until your out-of-pocket spending reaches $7,050. Then catastrophic coverage kicks in, and you pay only a small copayment (usually around $3.75 for generic drugs and $9.35 for brand-name drugs) for the rest of the year.

The numbers $5,030 and $7,050 are the 2024 thresholds and change each year. If you take expensive medications, you may hit the gap. If you take only a few inexpensive drugs, you may never reach it. Knowing where you fall helps you plan your budget. Some plans offer coverage in the gap to reduce your costs, though these plans usually have higher premiums.

Income-based subsidies that lower your costs

If your income is below 150% of the federal poverty level, you may receive a Low-Income Subsidy (LIS), also called "Extra Help." This program pays part or all of your premium, deductible, and copayments. In 2024, the income limit for a single person is roughly $1,468 per month, and for a married couple it is roughly $1,970 per month. These limits change each year.

To learn about you may have access to, contact your local Social Security office, call Social Security at 1-800-772-1213, or visit ssa.gov. You can also explore through your state Medicaid office. If you receive Supplemental Security Income (SSI) or Medicaid, you may be automatically enrolled in Extra Help. The subsidy is free and does not affect your other benefits.

How to compare plans and find your lowest cost

The best way to know what Part D will cost you is to use the Medicare Plan Finder tool on Medicare.gov. Enter your ZIP code, your current medications, and your pharmacy. The tool will show you every plan available in your area, ranked by estimated annual cost. You can see the premium, deductible, copayments for each of your drugs, and whether you will hit the coverage gap.

You can change plans once a year during the Annual Enrollment Period, which runs from October 15 to December 7. Your new coverage starts January 1. If you miss this window, you can only change plans if you have a may have access to life event — such as moving to a new state, losing other drug coverage, or becoming newly may be able to access for Medicare. Outside the enrollment period, you are locked into your current plan for the year.

Frequently Asked Questions

Can I get Part D coverage if I already have drug coverage from my employer?

You can, but you do not have to. If your employer coverage is as good as or better than Part D, you can skip Part D without penalty. If you drop it and later want to enroll, you may pay a penalty. Ask your employer's benefits department whether your coverage is "creditable" — that means it meets Medicare's standard.

What happens if I cannot afford my copayments?

Talk to your doctor or pharmacist about lower-cost alternatives, generic versions, or patient information programs run by drug manufacturers. If you may have access to for Extra Help (Low-Income Subsidy), your copayments may be much lower or free. You can also ask your plan about hardship exceptions or temporary payment plans.

Do I have to use a specific pharmacy?

Most plans have a network of pharmacies where your copayment is lowest. You can use an out-of-network pharmacy, but you will usually pay more. Check your plan's pharmacy list before you enroll, especially if you have a pharmacy you prefer.

What if my drug is not covered by my plan?

You can ask your plan for a formulary exception, which means asking them to cover a drug that is not on their list or to move it to a lower tier. Your doctor will need to submit the request and explain why the drug is medically necessary. The plan has 72 hours to respond in urgent cases and 7 days in standard cases.

Do Part D costs change every year?

Yes. Premiums, deductibles, copayments, and the list of covered drugs all change annually. Medicare announces the new costs in the fall, and you can change plans during the Annual Enrollment Period if a different plan will save you money.