Quick Answer
Medicare Part D helps cover prescription drug costs, but the amount you pay depends heavily on which plan you choose, which tier your drugs fall on, and whether you take advantage of available savings programs. Key strategies to minimize costs include comparing plans annually during the Annual Enrollment Period (October 15 – December 7), choosing generic drugs when possible, using mail-order pharmacies for maintenance medications, and applying for the Extra Help (Low Income Subsidy) program if you qualify. In 2026, the Part D out-of-pocket cap is $2,000 - the first time a hard cap has existed.
Coverage Comparison by Plan Type
| Plan Type | Coverage | Notes |
|---|---|---|
| Stand-Alone Part D (PDP) | Drug Coverage Only | Works alongside Original Medicare + Medigap. Covers prescription drugs only. Required if you have Original Medicare and want drug coverage. |
| Medicare Advantage + Drug (MAPD) | All-in-One Coverage | Combines Part A, Part B, and Part D in one plan. Most Medicare Advantage plans include drug coverage. Network restrictions apply. |
| Extra Help (LIS) | Subsidized Costs | Federal program for low-income beneficiaries. Reduces or eliminates Part D premiums, deductibles, and copays. Apply through Social Security. |
| State Pharmaceutical Assistance Programs (SPAPs) | State-Level Supplement | Some states offer additional drug cost assistance on top of Part D. Eligibility and benefits vary by state. |
Understanding Your Coverage Options
Understanding Part D Formularies and Drug Tiers
Every Medicare Part D plan has a formulary - a list of covered drugs organized into tiers. The tier your medication falls on determines how much you pay. Lower tiers (Tier 1 and Tier 2) are typically generic drugs with the lowest copays. Higher tiers (Tier 3 through Tier 5) include preferred brand-name, non-preferred brand-name, and specialty drugs, which carry significantly higher cost-sharing.
Formularies vary between plans and can change from year to year. A drug that was on Tier 2 this year may move to Tier 3 next year, increasing your cost. Plans are required to notify you of formulary changes, but it is your responsibility to review your plan's formulary each year during the Annual Enrollment Period to ensure your medications are still covered at an affordable tier.
What It Covers
- Tier 1 (Preferred Generic): Lowest copays - typically $0–$10/month
- Tier 2 (Generic): Low copays - typically $5–$20/month
- Tier 3 (Preferred Brand): Moderate copays - typically $35–$60/month
- Tier 4 (Non-Preferred Brand): Higher copays - typically $60–$100/month
- Tier 5 (Specialty): Highest cost-sharing - typically 25–33% coinsurance
- Prior authorization, step therapy, and quantity limits may apply to certain drugs
What It Doesn't Cover
- Drugs not on the formulary are not covered - you pay full price unless you get a formulary exception
- Formularies change annually - a covered drug this year may not be covered next year
- Discount programs like GoodRx do not count toward your Part D out-of-pocket spending
$ In 2026, the Part D out-of-pocket cap is $2,000. Once you reach $2,000 in out-of-pocket drug costs, you pay $0 for the rest of the year - a major improvement from prior years.
Always Check the Formulary before Enrolling
Before enrolling in any Part D plan, look up your specific medications on the plan's formulary at Medicare.gov or the plan's website. Verify the tier, any restrictions (prior authorization, step therapy), and the pharmacy network to estimate your true annual drug costs.
Part D Cost-Sharing: What You Pay
Part D cost-sharing has several components. Most plans charge a monthly premium, which varies by plan and location. The national base beneficiary premium in 2026 is $36.78/month, but actual plan premiums vary widely. High-income beneficiaries pay an additional Income-Related Monthly Adjustment Amount (IRMAA) on top of their plan premium.
Many Part D plans also have a deductible - the maximum standard deductible in 2026 is $590. Some plans waive the deductible for lower-tier drugs. After the deductible, you pay copays or coinsurance based on the drug's tier until you reach the $2,000 out-of-pocket cap, at which point your cost-sharing drops to $0 for the remainder of the year.
What It Covers
- Monthly premium: varies by plan (average ~$36.78/month in 2026)
- Annual deductible: up to $590 in 2026 (some plans waive for Tier 1/2 drugs)
- Copays/coinsurance: based on drug tier (see tier breakdown above)
- Out-of-pocket cap: $2,000 in 2026 - after this, you pay $0 for covered drugs
- Medicare Prescription Payment Plan: option to spread costs across monthly installments
What It Doesn't Cover
- IRMAA surcharge applies if your income exceeds $106,000 (individual) or $212,000 (joint) in 2026
- Drugs not on the formulary are not covered by cost-sharing protections
- Discount card purchases (GoodRx, etc.) do not count toward the $2,000 cap
$ IRMAA for Part D in 2026 ranges from $13.70 to $85.80/month added to your plan premium, depending on your income. Check your income bracket at Medicare.gov.
The $2,000 Cap is New in 2026 - a Major Benefit
Starting in 2026, there is a hard $2,000 annual out-of-pocket cap on Part D drug costs. This is a significant change from prior years when there was effectively no cap for most beneficiaries. Once you hit $2,000 in out-of-pocket costs, you pay $0 for covered drugs for the rest of the year.
Top Strategies to Minimize Part D Costs
There are several proven strategies to reduce your out-of-pocket prescription drug costs under Medicare Part D. The most impactful is comparing plans every year during the Annual Enrollment Period (October 15 – December 7). Part D plans change their formularies, premiums, and pharmacy networks annually. A plan that was the best value last year may not be the best value this year. Use the Medicare Plan Finder at Medicare.gov to compare plans based on your specific medications.
Other high-impact strategies include requesting generic substitutions from your doctor, using mail-order pharmacies for 90-day supplies of maintenance medications (which typically cost less per dose than 30-day retail fills), and applying for the Extra Help program if your income and assets are below the eligibility thresholds. Extra Help can reduce your Part D costs to near zero if you qualify.
What It Covers
- Compare plans annually at Medicare.gov using the Plan Finder tool with your specific drug list
- Request generic alternatives - generics cost 80–85% less than brand-name equivalents
- Use mail-order pharmacy for 90-day supplies of maintenance medications
- Apply for Extra Help (LIS) if income is below ~$22,590 (individual) or ~$30,660 (couple) in 2026
- Check for State Pharmaceutical Assistance Programs (SPAPs) in your state
- Ask your doctor about manufacturer patient assistance programs for high-cost specialty drugs
- Use preferred pharmacies in your plan's network for lower copays
- Review your plan's formulary each fall before the AEP deadline
What It Doesn't Cover
- GoodRx and other discount programs do not count toward your $2,000 out-of-pocket cap - use them strategically for drugs not covered by your plan
- Switching plans mid-year is generally not allowed except during Special Enrollment Periods
$ Mail-order pharmacies often provide a 90-day supply for the same cost as a 60-day retail supply - effectively a 33% savings on maintenance medications. Check if your plan has a preferred mail-order pharmacy.
Extra Help Can Save Thousands per Year
The Extra Help (Low Income Subsidy) program can reduce Part D premiums, deductibles, and copays to near zero for qualifying beneficiaries. In 2026, you may qualify if your annual income is below approximately $22,590 (individual) or $30,660 (couple). Apply through the Social Security Administration at ssa.gov or call 1-800-772-1213.
Part D Cost-Sharing Summary (2026)
| Cost Component | 2026 Amount | Notes |
|---|---|---|
| Monthly Premium | Varies by plan (~$36.78 avg) | Higher-income beneficiaries pay IRMAA surcharge on top |
| Annual Deductible | Up to $590 | Some plans waive deductible for Tier 1/2 drugs |
| Tier 1 Copay (Preferred Generic) | $0–$10 | Lowest cost-sharing; most generic drugs |
| Tier 2 Copay (Generic) | $5–$20 | Standard generic drugs |
| Tier 3 Copay (Preferred Brand) | $35–$60 | Preferred brand-name drugs |
| Tier 4 Copay (Non-Preferred Brand) | $60–$100+ | Non-preferred brand-name drugs |
| Tier 5 Coinsurance (Specialty) | 25–33% coinsurance | High-cost specialty drugs; subject to $2,000 cap |
| Out-of-Pocket Cap | $2,000 | NEW in 2026 - after $2,000, you pay $0 for covered drugs |
| Extra Help (LIS) Copays | $0–$11.20 (specialty) | For qualifying low-income beneficiaries |
✦ What to do if Your Drug is not Covered
Request a Formulary Exception
If your medication is not on your plan's formulary, you can file a formulary exception request. Your doctor must provide documentation showing the drug is medically necessary and that covered alternatives are not appropriate for your condition. Approval is not guaranteed, but exceptions are granted when medical necessity is clearly documented.
Your doctor must submit supporting documentation - start the process as early as possible
Request a Tier Exception
If your drug is on the formulary but at a high tier, you can request a tier exception to have it covered at a lower tier's cost-sharing level. Your doctor must document why a lower-tier alternative is not medically appropriate. Tier exceptions can result in significant savings for brand-name drugs.
Tier exceptions can reduce your copay from $60–$100+ to $35–$60 or lower
Explore Manufacturer Patient Assistance Programs
Many pharmaceutical manufacturers offer patient assistance programs (PAPs) for high-cost brand-name and specialty drugs. These programs can provide the medication at low or no cost for qualifying patients. Contact the manufacturer directly or visit NeedyMeds.org to find available programs for your specific medications.
Manufacturer PAPs can provide specialty drugs at little or no cost for qualifying patients
✦ Frequently Asked Questions
David Haass
AuthorDavid Haass is the Chief Technology Officer and Co-Founder of Elite Insurance Partners and MedicareFAQ.com. He is a member and regular contributor to Forbes Finance Council and stays up-to-date with the latest Medicare trends and changes.
Ashlee Zareczny
ReviewerAshlee Zareczny is the Compliance and Editorial Manager at MedicareFAQ, ensuring all Medicare content is accurate, up-to-date, and compliant with CMS guidelines.