Trace your Part D spending through all four phases and see why the $2,000 threshold does not cap what you pay — plus why brand-name drugs can cost less than generics.
| Annual Retail Cost | Deductible | Initial Phase | Coverage Gap | Catastrophic | You Pay | Saving vs Retail |
|---|---|---|---|---|---|---|
| $6,000 brand | $590 | $352 | $278 | $72 | $1,293 | 78.5% |
| $9,800 brand | $590 | $352 | $278 | $167 | $1,388 | 85.8% |
| $9,800 generic | $590 | $352 | $1,058 | $89 | $2,089 | 78.7% |
| $20,000 brand | $590 | $352 | $278 | $422 | $1,643 | 91.8% |
| $60,000 brand | $590 | $352 | $278 | $1,422 | $2,643 | 95.6% |
Every row is produced by the same phase model the calculator runs. The two $9,800 rows are the key comparison: identical retail cost, but the brand-name patient pays $1,388 while the generic patient pays $2,089. The 70% manufacturer discount on brand drugs counts toward the $2,000 threshold, so brand patients reach catastrophic coverage quickly and then pay only 2.5% — while generic patients must climb the gap using their own 25% alone.
| Phase | Ends when | You Pay |
|---|---|---|
| Deductible | $590 of retail is spent | 100% |
| Initial coverage | Total retail drug cost reaches $2,000 | 25% of retail |
| Coverage gap / manufacturer discount | Your TrOOP reaches $2,000 | 25% of retail |
| Catastrophic | All year | 2.5% of retail |
Before 2025 the gap was a percentage band: after $5,030 of total drug costs you paid 25% of brand drugs until your out-of-pocket hit roughly $8,000. The Inflation Reduction Act replaced that with a $2,000 TrOOP threshold and pulled the manufacturer discount into the gap itself. The name "donut hole" survives in common use, but there is no longer any phase where you pay full retail after the deductible.
In the gap phase, every dollar of brand-name retail cost adds 25 cents of your money and 70 cents of manufacturer discount to your TrOOP counter — 95 cents of progress per dollar. For generics only your own 25 cents counts. A brand-heavy patient therefore reaches the $2,000 threshold after roughly $2,100 of gap spending, while a generic-only patient needs about $4,200. That single mechanical difference explains why switching one drug to a generic can, counter-intuitively, increase your total out-of-pocket spending.
Ask the prescriber whether a preferred-tier alternative exists — moving one brand drug to a lower tier can keep you out of the gap entirely. Confirm you are using the plan's preferred pharmacy, which can cut the initial-phase copay by a third. Then check Extra Help eligibility through Social Security: the income and resource limits are higher than most people assume, and full subsidy eliminates the gap rather than merely softening it.
Since 2025 Medicare Part D has advertised a $2,000 out-of-pocket cap, and most enrollees assume their drug costs stop there. They do not. The $2,000 is the true-out-of-pocket threshold that moves you into catastrophic coverage, where you still pay 2.5% of the retail price with no upper limit. On $60,000 of brand drugs that 2.5% adds $1,422 on top of the $1,221 you already paid — a total of $2,643, not $2,000. This calculator shows all four phases so you can see which one is actually costing you.
The 70% manufacturer discount applies only to brand drugs, and it counts toward your $2,000 threshold as though you had paid it. That is the whole ballgame. Two patients with the same $9,800 retail bill pay $1,388 and $2,089 depending on whether their drugs are brand or generic — the brand patient pays less out of pocket because the discount accelerates them into the cheap catastrophic phase. When comparing plans, this is the most useful thing to model.
Pull your drug list and check the tier each drug sits on in every plan you are considering. A drug that is tier 3 in one plan and tier 2 in another can move your entire year out of the gap. Confirm the pharmacy too, since preferred pharmacies within a network can cut initial-phase copays by a third. Finally apply for Extra Help even if you think you earn too much — the limits are more generous than most people expect, and the subsidy removes the gap rather than merely reducing it.
⚠️ Important: Uses 2025 standard Part D parameters: $590 deductible, the initial coverage phase ending at $2,000 of total retail drug cost, a $2,000 true-out-of-pocket catastrophic threshold, and 2.5% catastrophic coinsurance. Real costs depend on your plan formulary tiers, negotiated prices, pharmacy network and whether the deductible applies to each tier. Planning estimate only, not a substitute for your plan Summary of Benefits.