How Much Does Medicare Part D Cost in 2026? Premiums, Deductible & Phases

"How much will Part D cost me?" is the first question most people ask — and the honest answer is: it depends on your plan and your prescriptions. But the federal standard benefit sets clear boundaries, so you can estimate with confidence.

The four cost pieces

1. Monthly premium

Set by your insurer, not by Medicare. Premiums vary widely by plan and region — from under $10 to well over $100 per month. People with higher incomes may also pay an Income-Related Monthly Adjustment Amount (IRMAA) surcharge on top of the plan premium.

2. Annual deductible — up to $615 in 2026

You pay 100% of your covered drug costs until you meet your plan's deductible. The maximum any plan can charge is $615 in 2026, but many plans set a lower deductible — and some waive it entirely, especially for lower drug tiers.

3. Copays and coinsurance

After the deductible, you share costs with your plan until your out-of-pocket spending reaches $2,100. Under the standard benefit that's roughly 25% coinsurance, but most plans use flat copays by tier (for example: $5 preferred generic, $45 preferred brand, higher for specialty).

4. Catastrophic coverage — $0

Once your qualifying out-of-pocket spending hits $2,100 in 2026, you pay nothing for covered Part D drugs for the rest of the calendar year. There is no longer any coinsurance in catastrophic coverage.

The three coverage phases at a glance

1. Deductible — you pay full cost up to your plan's deductible (max $615).
2. Initial coverage — you pay copays/coinsurance; the plan pays its share. Continues until your out-of-pocket total reaches $2,100.
3. Catastrophic — $0 for covered drugs through December 31.

(The old fourth phase, the "donut hole" coverage gap, was eliminated in 2025.)

Built-in protections worth knowing

• Insulin: covered insulin products cost no more than $35 for a month's supply — and the deductible doesn't apply.
• Vaccines: adult vaccines recommended by the CDC's advisory committee (like shingles and Tdap) are $0 under Part D.
• Payment smoothing: the Medicare Prescription Payment Plan lets you spread out-of-pocket costs into monthly payments across the year instead of paying big sums at the pharmacy.

What does NOT count toward the $2,100 cap

Your monthly premium never counts. Neither do drugs your plan doesn't cover, or drugs bought outside your plan's network or coverage rules. Only qualifying out-of-pocket spending on covered drugs moves you toward catastrophic coverage.

Bottom line: In 2026, the most you can pay out-of-pocket for covered Part D drugs is $2,100 (plus premiums) — then the rest of the year is $0. Compare plans on total annual cost for your drug list, not just the premium.