Prescription Costs & Part D
What is the Medicare drug cost cap in 2026?
Last reviewed: · Big Sioux Benefits Data Desk
In 2026 you will not pay more than $2,100 out of pocket for covered prescription drugs under Medicare Part D (CMS CY2026 Part D benefit parameters). Once your out-of-pocket spending reaches that threshold, you pay $0 for covered drugs for the rest of the calendar year. The cap applies whether your drug coverage comes through a standalone Part D plan or is bundled into a Medicare Advantage plan.
The qualifier: the cap covers what you pay for covered drugs, and the word covered is doing real work. Your monthly premium does not count toward it. Neither does anything you spend on a drug your plan does not cover, on a drug bought outside your plan with a discount card, or on drugs billed under Part B rather than Part D. What does count is your deductible and your cost sharing on covered prescriptions, plus certain payments made on your behalf, including through Extra Help.
What counts toward the $2,100
| Spending | Counts toward the cap? |
|---|---|
| Your Part D deductible | Yes |
| Your copays and coinsurance on covered drugs | Yes |
| Payments made on your behalf, including through Extra Help | Yes |
| Your monthly plan premium | No |
| Drugs your plan does not cover | No |
| Drugs bought with a discount card instead of your plan | No |
| Drugs billed under Medicare Part B | No, Part B has its own rules |
This is the single largest change to Medicare drug coverage in a generation. Before 2025 there was no limit at all, and a person on one specialty drug could face five figures a year with no ceiling in sight. The practical effect now is that the worst case is knowable in advance. For when in the year most people reach it, see when you hit the cap; if paying it all at once in January is the problem, the Medicare Prescription Payment Plan spreads it across the year at no added cost. We walk through what the cap means locally in the Sioux Falls guide to the Part D cost cap, and drug coverage generally in Part D prescription drug plans.
Sources
- CMS — Announcement of Calendar Year 2026 Medicare Advantage Capitation Rates and Part C and Part D Payment Policies (Part D benefit parameters) — CY2026 parameters; accessed 2026-08-21
- Medicare.gov — Costs for Medicare drug coverage — accessed 2026-08-21
- Medicare.gov — Help with drug costs (Extra Help) — 2026 limits and amounts; accessed 2026-08-21
Related questions
Does the $2,100 cap include my monthly plan premium?
No. Premiums never count toward the out-of-pocket threshold. The cap covers what you pay at the pharmacy counter for covered drugs, meaning your deductible and your cost sharing, along with certain payments made on your behalf such as Extra Help. You keep paying your premium every month even after you reach the cap.
Does the cap reset each year?
Yes, on January 1. The out-of-pocket total starts again at zero every calendar year, which is why people on expensive drugs often see a large bill in January and very small ones later in the year. The Medicare Prescription Payment Plan exists specifically to smooth that pattern.
Drug costs turn on your specific prescriptions, so the arithmetic is worth doing once, properly: book a free, no-pressure conversation, see your county's South Dakota plan lineup, or browse all answers. SHIINE, the state's free counseling program, is at 1-800-536-8197 and sells nothing.
Big Sioux Benefits is a licensed insurance agency, not affiliated with or endorsed by the U.S. government or the federal Medicare program. We do not offer every plan available in your area. Contact Medicare.gov, 1-800-MEDICARE, or SHIINE (South Dakota's SHIP) for all of your options.