How Medicare Part D Prescription Drug Plans Work in 2026

Medicare Part D covers prescription drugs with a new $2,000 out-of-pocket cap in 2026, but choosing the right plan depends on your specific medications.

Author: Lynsey Brennan, Licensed Medicare Advisor | Published May 19, 2026 Reading time: 6 min read

Quick Answer

Part D plans are standalone prescription drug coverage you add to Original Medicare or built into Medicare Advantage plans. In 2026, all Part D plans have a $2,000 maximum out-of-pocket limit, meaning once you've spent that amount on covered drugs, you pay nothing for the rest of the year. Your premium, formulary, and pharmacy network determine what you actually pay month to month.

Table of Contents

• What Part D Actually Covers
• The 2026 Out-of-Pocket Cap Changes Everything
• How to Find Your Drugs on a Plan's Formulary
• Standalone Part D vs. Medicare Advantage with Drug Coverage
• What Florida Seniors Pay for Part D in 2026
• When You Can Enroll or Switch Plans

What Part D Actually Covers

Part D covers prescription drugs you pick up at the pharmacy or get through mail order. It does not cover drugs given to you during a hospital stay or at the doctor's office — those fall under Part A or Part B.

Every Part D plan has a formulary, which is the list of drugs it covers. Plans place drugs into tiers, usually five of them. Tier 1 drugs (mostly generics) cost the least. Tier 5 drugs (specialty medications) cost the most. If your drug isn't on a plan's formulary, you'll pay full price unless you get an exception approved.

Plans also control where you fill prescriptions. Some require you to use specific pharmacies to get the lowest price. Others charge more if you go out of network.

The 2026 Out-of-Pocket Cap Changes Everything

Starting in 2026, all Part D plans have a $2,000 annual out-of-pocket maximum. Once you've spent $2,000 on covered drugs in a calendar year, you pay $0 for the rest of the year.

This is a big deal if you take expensive medications. Before 2026, people in the catastrophic phase still paid 5% of drug costs with no limit. Someone on a $10,000-per-month specialty drug could pay $6,000+ out of pocket annually. Now it stops at $2,000.

The catch: not every dollar you spend counts toward the $2,000. Your monthly premium doesn't count. Drugs not on your formulary don't count. What does count are your copays, coinsurance, and deductible for covered drugs.

How to Find Your Drugs on a Plan's Formulary

Go to Medicare.gov/plan-compare and enter your medications. The tool shows which plans cover your drugs, what tier they're on, and your estimated annual cost.

Don't skip this step. I've seen people in Palm Beach County pick a $0 premium Part D plan only to discover their insulin is Tier 4 and costs $150 a month. A plan with a $30 premium might have put that same insulin on Tier 2 for $15 a month.

Call the plan directly if your drug is brand-name and expensive. Ask if there's a generic alternative on a lower tier or if they require step therapy (trying cheaper drugs first). Some plans require prior authorization for certain medications, which means your doctor has to justify why you need it before they'll cover it.

Standalone Part D vs. Medicare Advantage with Drug Coverage

If you have Original Medicare, you add a standalone Part D plan. Premiums in Florida range from $0 to about $90 per month depending on the plan.

If you have a Medicare Advantage plan, drug coverage is usually built in (these are called MAPD plans). You can't add a standalone Part D to a Medicare Advantage plan — it's one or the other.

The trade-off: Medicare Advantage plans with drug coverage often have low or $0 premiums, but they restrict you to network doctors and hospitals. Original Medicare with Part D and a Medigap plan (like Plan G, which runs around $145-$180 per month in Palm Beach County) costs more upfront but lets you see any doctor who takes Medicare nationwide.

According to the Kaiser Family Foundation, only 30% of Medicare beneficiaries review their plan annually during the Annual Enrollment Period. That's a mistake, especially if your medications or health changed during the year.

What Florida Seniors Pay for Part D in 2026

Most people pay the standard Part D premium, which averages $40-$50 per month in Florida for 2026. If your income is above $106,000 (single) or $212,000 (married), you pay an extra Income-Related Monthly Adjustment Amount (IRMAA) on top of your premium. IRMAA ranges from $12.90 to $81 per month depending on your income.

In South Florida, I see a lot of plans in the $20-$35 per month range with decent formularies. The $0 premium plans exist but usually have higher copays or fewer preferred pharmacies.

Most plans also have a deductible, up to $590 in 2026. After you pay the deductible, you enter the initial coverage phase where you pay copays until you hit that $2,000 out-of-pocket cap.

When You Can Enroll or Switch Plans

You get a one-time enrollment period when you first get Medicare Part A and B. If you miss it, you may pay a late penalty — 1% of the national base premium for every month you went without coverage.

Annual Enrollment Period (AEP) runs October 15 to December 7 every year. This is when you can switch Part D plans or move between Original Medicare and Medicare Advantage. Changes take effect January 1.

There's also a Medicare Advantage Open Enrollment Period from January 1 to March 31, but it's only for people already on Medicare Advantage who want to switch plans or drop back to Original Medicare.

Frequently Asked Questions

Q: Can I use any pharmacy with Part D? A: Most plans have preferred pharmacy networks. You can use out-of-network pharmacies, but you'll pay more. Check your plan's pharmacy list before filling a prescription, especially for expensive medications.

Q: What happens if my drug isn't covered? A: You can ask your doctor to request an exception or prior authorization. If the plan denies it, you pay full price or find an alternative drug that's covered. Sometimes switching to a different Part D plan during AEP makes more sense.

Q: Do I need Part D if I have VA or Tricare coverage? A: No. VA, Tricare, and most employer plans count as creditable coverage. You won't pay a late penalty as long as you keep that coverage. But compare costs — sometimes Part D is cheaper than what you're currently paying.

Q: Can I drop Part D if I don't take any medications? A: You can, but if you go 63 days or more without creditable drug coverage and later decide to enroll, you'll pay a late penalty for as long as you have Part D. Even if you're healthy now, it's usually smarter to keep a low-cost plan.

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