Medicare prescription drug coverage
Part D prescription drug plans, explained clearly
Part D prescription drug plans cover the medications Original Medicare does not. You get them either as a standalone policy or built into a Medicare Advantage plan. This page explains how Part D prescription drug plans work, what the 2026 numbers actually are, why the formulary matters far more than the premium, and how the late penalty is calculated.
The two ways to get Part D prescription drug plans
Prescription coverage is not built into Original Medicare. You add it, and there are exactly two routes.
A standalone Part D plan
Bought separately and paired with Original Medicare, usually alongside a Medigap policy. You hold two or three cards and choose your drug plan independently of everything else.
Built into a Medicare Advantage plan
Most Medicare Advantage plans include drug coverage. One card, one plan, but your drug coverage is tied to your medical plan. Changing one means changing both.
You cannot hold a standalone Part D plan and a Medicare Advantage plan that already includes drug coverage. Enrolling in a standalone plan can automatically disenroll you from your Medicare Advantage plan, which is a costly surprise if it was not intended.
What Part D prescription drug plans cost in 2026
Several numbers are set federally each year and apply no matter which plan you choose.
- The maximum annual Part D deductible a plan may charge is $615
- The annual out-of-pocket cap is $2,100, up from $2,000 the previous year
- The standard Part B premium is $202.90 per month, or higher depending on income
- The Part B annual deductible is $283
- The Part A hospital deductible is $1,736 per benefit period
Plan premiums sit on top of these and vary widely. Amounts change every year, so confirm the current figures at Medicare.gov before relying on them.
The out-of-pocket cap changed the math
For years, Part D had no ceiling. Someone on an expensive specialty medication could pay indefinitely. The cap ended that. Once your out-of-pocket drug spending reaches $2,100 in a calendar year, you pay nothing more for covered drugs for the rest of that year.
This matters most for people on high-cost brand-name or specialty drugs, who now have a worst case they can actually plan around.
How the coverage stages work
Deductible stage
If your plan has a deductible, you pay the full negotiated price until you meet it. Some plans set it at zero, some at the maximum, and many exclude lower drug tiers from the deductible entirely.
Initial coverage stage
You pay a copay or coinsurance for each prescription and the plan pays the rest. What you pay depends on the drug’s tier.
Catastrophic stage
Once your out-of-pocket spending reaches the annual cap, you pay nothing for covered drugs for the remainder of the year.
The old coverage gap, widely known as the donut hole, no longer works the way most people remember. If someone describes Part D using donut hole language, they are describing an earlier version of the program.
Spreading the cost across the year
Medicare now offers a payment option that lets you spread your out-of-pocket drug costs into monthly payments across the calendar year rather than paying large amounts at the pharmacy counter. It does not reduce what you owe overall, but it smooths the timing, which helps people whose costs land early in the year. Details are at Medicare.gov.
The formulary matters more than the premium on Part D prescription drug plans
This is the single most common and most expensive mistake in Part D. People compare monthly premiums, pick the cheapest, and discover in February that a medication sits on a tier they cannot afford.
Every plan has its own drug list
The same medication can sit on tier 2 in one plan and tier 4 in another sold on the same street. The tier decides what you pay.
Restrictions apply too
Prior authorization, step therapy and quantity limits can all apply. A drug can be on the formulary and still be difficult to obtain.
Pharmacy networks and preferred pricing
Part D prescription drug plans contract with pharmacies, and most divide them into preferred and standard tiers.
At a preferred pharmacy your copay is lower. At a standard in-network pharmacy the same drug costs more. Out of network, the plan may not pay at all.
Check that the pharmacy you actually use is preferred, not merely in network. For someone filling several prescriptions monthly, that distinction adds up quickly across a year.
Mail order is often the cheapest route for maintenance medications, frequently offering a 90-day supply for roughly the cost of two months at retail.
The Part D late enrollment penalty
If you go 63 days or more without Part D or other creditable prescription coverage after your Initial Enrollment Period, Medicare adds a permanent penalty to your premium.
The penalty is calculated as roughly one percent of the national base beneficiary premium for each month you went without, and it is added to your premium for as long as you have Part D coverage.
It does not go away when you finally enroll, and it grows the longer you wait. This is why people who take no medication at all are still generally advised to take a low-cost plan.
Creditable coverage from an employer, a union, or the VA counts and prevents the penalty. Keep the letter confirming it, because you may need to prove it later.
Help paying for Part D prescription drug plans
Extra Help, also called the Low Income Subsidy, substantially lowers premiums, deductibles and copays for people with limited income and resources. It can also erase a late enrollment penalty.
You can check eligibility and apply directly through the Social Security Administration. Many people who qualify never apply, so it is worth checking even if you assume you earn too much.
Qualifying for Medicaid usually brings Extra Help automatically. Our dual eligibility page explains how the programs interact.
State Pharmaceutical Assistance Programs exist in some states as an additional layer of help.
How to compare Part D prescription drug plans
Work from your medication list, not from the premium column.
- Write down every prescription with the exact dose and how often you take it
- Enter that list into the official finder at Medicare.gov Plan Compare, which prices plans against your actual drugs
- Check each drug’s tier and any prior authorization or step therapy requirement
- Confirm your pharmacy is a preferred pharmacy, not just in network
- Compare estimated total annual cost, not the monthly premium
Do this every year. Formularies and tiers reset each January, and the plan that was cheapest for your drug list last year frequently is not this year.
Free unbiased counseling is available through your State Health Insurance Assistance Program.
Ask before you decide
Frequently asked questions about Part D prescription drug plans
Do I need Part D if I take no medication?
Generally yes, unless you have other creditable coverage. Going without triggers a permanent late enrollment penalty, so a low-cost plan is usually cheaper than waiting.
Can I have a standalone Part D plan with Medicare Advantage?
Not if your Medicare Advantage plan already includes drug coverage. Enrolling in a standalone plan can automatically disenroll you from that plan.
What happened to the donut hole?
The coverage gap no longer works as it once did. There is now an annual out-of-pocket cap, $2,100 in 2026, after which you pay nothing for covered drugs that year.
Can I change plans mid-year?
Usually only during Annual Enrollment, October 15 to December 7, unless you qualify for a Special Enrollment Period through a move, a loss of coverage, or Medicaid eligibility.
My drug is not on the formulary. What now?
You can request a formulary exception from the plan, ask your prescriber about a covered alternative, or change plans at the next enrollment opportunity.
Does your help cost anything?
No additional fee is charged to you for O’Neal Insurance Group’s guidance. Agents may be compensated by an insurance carrier when an enrollment occurs.
Important: Federal cost figures cited are for the 2026 plan year and change annually; confirm current amounts at Medicare.gov. Plan availability, formularies, pharmacy networks and costs vary by plan and by year. Nothing on this page is an offer of coverage or a statement of what any specific plan provides. We do not offer every plan available in your area. Any information we provide is limited to those plans we do offer in your area. Please contact Medicare.gov, 1-800-MEDICARE, or your State Health Insurance Assistance Program to get information on all of your options.
Official resource
The 2026 numbers behind Part D prescription drug plans
The maximum deductible a plan may charge in 2026 is $615, though many charge less or none at all. Out-of-pocket spending on covered drugs is capped at $2,100 for the year. Once you reach that ceiling you pay nothing more for covered drugs until January.
That cap is the single largest change to Part D prescription drug plans in a generation. It replaced the old coverage gap, and for anyone on expensive medication it converts an unpredictable year into a known worst case. If you have been avoiding a drug because of what it cost in a bad month, the arithmetic has changed and is worth revisiting.
Insulin is capped separately at no more than $35 for a month’s supply. The national base beneficiary premium used in penalty and subsidy calculations is $38.99 for 2026, which is not what any particular plan charges but is the figure the formulas run on.
The surcharge higher earners pay
If your income is above the threshold you pay an income-related adjustment on top of your plan’s premium, based on your 2024 tax return. It runs from $14.50 a month for single filers above $109,000 up to $91.00 a month at $500,000 or more.
It is paid to Medicare rather than to the plan, so switching plans does not avoid it. If your income has dropped since 2024 for a qualifying reason, form SSA-44 asks Social Security to use current figures instead.
Spreading Part D prescription drug plans costs across the year
All Part D prescription drug plans are now required to offer a monthly installment option, the Medicare Prescription Payment Plan. Instead of paying a large amount at the pharmacy counter in January, your annual out-of-pocket drug costs are spread across the remaining months of the year in predictable payments.
It does not reduce what you pay. It changes when you pay it. That suits someone facing a heavy bill early in the year on a fixed monthly income, and it does nothing useful for someone whose drug costs are modest and evenly spread.
Two things to know before opting in. You must enroll in the program — it is not automatic. And if you join partway through the year, the balance is spread across fewer remaining months, so the installments are larger than they would have been in January.
Extra Help with Part D prescription drug plans, and why people who qualify never apply
Extra Help, also called the Low Income Subsidy, is the single most valuable thing available to anyone on Part D prescription drug plans who is near the income limits. For 2026 the income limit is about $23,940 for one person and $32,460 for a couple, with resource limits near $18,090 and $36,100.
What it delivers is substantial. There is no deductible. Cost sharing drops to a few dollars per prescription — for 2026 that is $1.60 for a generic and $4.90 for a brand-name drug for those at the lowest income level, and $5.10 and $12.65 for others — and nothing at all once you pass the $2,100 annual cap. The late enrollment penalty is waived.
One change deserves emphasis because it happened quietly. The partial subsidy was abolished at the start of 2024. Before that, people just over a line received a reduced benefit. Now everyone who qualifies receives the full subsidy, which moved a large number of households from modest help to substantial help without their being told.
Not all income counts and not all assets count. Your home and your car are generally excluded, and several states apply more generous rules than the federal floor. If you have ever looked at the limits, decided you were over them, and moved on, it is worth ten minutes to check again rather than assume.
People who receive Medicaid, Supplemental Security Income, or a Medicare Savings Program are automatically deemed eligible and do not need to apply separately. Everyone else applies through Social Security, and applying costs nothing.
What changes each year, and what does not
Formularies, tiers, pharmacy networks and premiums are all reset annually, and plans notify you each autumn in the Annual Notice of Change. The document is dry and it is the most useful piece of post you receive all year, because it lists exactly what is different about your own plan.
A drug moving up a tier, a pharmacy leaving the preferred network, or a new prior authorization requirement can change your annual cost by more than any premium difference between competing Part D prescription drug plans. That is the case for re-checking every year rather than letting a plan renew unexamined.
The mistake we see most often
People choose Part D prescription drug plans on the monthly premium. It is the number displayed largest and the only one that is easy to compare, so it is the one that decides.
For anyone taking regular medication it is close to the least important figure. A plan charging nothing a month can cost more over a year than one charging twenty dollars, if a single drug sits on a higher tier or needs prior authorization. The comparison that matters runs your actual prescriptions, at your actual doses, through your actual pharmacy, and produces an annual total. Every serious comparison of Part D prescription drug plans starts there, and it takes minutes rather than hours.
Check the source, then ask for personal help
Educational information is general. A licensed agent can help with plan comparisons; agents do not provide medical, legal, or official eligibility advice.
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Compare Part D prescription drug plans against your actual medication list
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