Medicare Part D — Key Facts for 2026
| Detail | 2026 Amount |
|---|---|
| Standard Part D deductible (max) | $590/year |
| Initial coverage limit | $2,000 (after this, catastrophic phase begins) |
| Catastrophic coverage phase | $0 copay for covered drugs (new 2025) |
| Low-income subsidy (Extra Help) | $0–$15 copays for qualifying beneficiaries |
| Average Part D premium | $46/month |
| Penalty for late enrollment | 1% of national base premium per month late |
Understanding Drug Formularies
Every Part D plan has a formulary — a list of covered drugs organized into tiers. Higher tiers mean higher cost-sharing. The five standard tiers are:
- Tier 1 — Preferred generics: Lowest copay ($0–$5)
- Tier 2 — Non-preferred generics: $5–$15 copay
- Tier 3 — Preferred brand drugs: $35–$47 copay
- Tier 5 — Specialty drugs: 25–33% coinsurance (high-cost medications)
Before enrolling in any Part D plan, enter all your medications into Medicare.gov's Plan Finder. It shows exactly what each drug costs under each available plan — the total annual drug cost including premiums, deductibles, and copays.
The IRA $2,000 Out-of-Pocket Cap (2025+)
The Inflation Reduction Act capped Medicare Part D out-of-pocket drug costs at $2,000/year starting in 2025. Once you've paid $2,000 in covered drug costs, Medicare covers 100% of remaining costs for the year. This eliminated the "donut hole" coverage gap and provides significant relief to beneficiaries on high-cost specialty medications.
Frequently Asked Questions
You should enroll when first eligible even if you take no medications — the late enrollment penalty (1% per month late) accumulates permanently. A low-premium plan ($15–$20/month) protects you from the penalty while minimizing current cost. If you later need expensive medications, you'll be glad you enrolled on time.
Yes — during Medicare Open Enrollment (October 15 – December 7), you can switch Part D plans with coverage starting January 1. This is important because formularies, premiums, and drug costs change annually. Review your current plan's Annual Notice of Change (sent in September) and compare alternatives each fall.
You have several options: request a formulary exception (your doctor must document medical necessity), use a different drug in the same class that is on formulary, switch plans during Open Enrollment, or use GoodRx or manufacturer patient assistance programs as an alternative to insurance for some non-covered drugs.