How to Plan Annual Open Enrollment for Medication Coverage in Medicare
Don’t Assume Your Medicare Drug Plan Stays the Same
Every year, your Medicare prescription drug plan changes-sometimes dramatically. A medication that cost $10 last year might jump to $120 this year. Your local pharmacy could drop out of the network. A drug you rely on might move from Tier 2 to Tier 4, meaning you pay three times as much. If you don’t review your coverage during Annual Open Enrollment, you could be paying hundreds or even over a thousand dollars extra for the same meds.
The window to fix this is short: October 15 to December 7 each year. Changes you make during this time take effect on January 1. For 2026 coverage, that means you need to act between October 15, 2025, and December 7, 2025. Missing the deadline means you’re stuck with your current plan until next year-even if your insulin just got 50% more expensive.
Start by Listing Every Medication You Take
Before you even look at a plan, write down every prescription you take. Include the name, dosage, and how often you take it. Don’t forget over-the-counter meds if they’re part of your daily routine and covered under your plan. For example, if you take metformin 500mg twice daily, lisinopril 10mg once a day, and a monthly GLP-1 like Ozempic, list them all. Some plans treat these differently, and missing one can blow up your budget.
Pro tip: Use the pill organizer you already have. Count how many pills you go through in a month. That’s your real usage-not what you think you take. Many people forget they refill a medication early or skip doses, which skews cost estimates.
Get Your Annual Notice of Change (ANOC)
By September 30, your current plan should mail you the Annual Notice of Change. Don’t ignore it. This document tells you exactly what’s changing for 2026: new premiums, higher deductibles, removed drugs from the formulary, or pharmacy network cuts. It’s the only official source for what’s changing with your current plan.
Look for three things:
- Formulary changes: Did your drug get moved to a higher tier? Was it removed entirely?
- Cost changes: Did your monthly premium go up? What about your copay for your top three meds?
- Network changes: Is your pharmacy still in-network? Was your preferred pharmacy downgraded to "standard"?
According to Medicare Rights Center data, 78% of Medicare Advantage plans changed their provider networks between 2023 and 2024. If your pharmacy isn’t on the list anymore, you’ll pay more-or have to drive farther.
Use the Medicare Plan Finder Tool
Go to Medicare.gov/plan-compare and enter your zip code, medications, and preferred pharmacy. The tool lets you compare every plan available in your area side-by-side.
Here’s what to focus on:
- Enter your exact medications and dosages. The tool calculates your estimated annual drug cost based on real data.
- Sort by "Total Drug Cost"-not monthly premium. A $0 premium plan with a $500 deductible and high copays on your meds could cost you more than a $40/month plan with low copays.
- Check the formulary tier for each drug. Tier 1 is cheapest. Tier 5 (specialty) is most expensive.
- Verify your pharmacy is "preferred" in the network. Preferred pharmacies usually cut your copay by 20-40%.
Beneficiaries who use this tool are 3.2 times more likely to find a cheaper plan than those who don’t. One woman in Birmingham switched from a plan where her Ozempic cost $1,200/year to one where it cost $350-just by checking the formulary tier.
Watch Out for the Hidden Traps
Not all savings are what they seem. Here are the three biggest traps:
1. The "Low Premium, High Copay" Trap
A plan with a $0 premium might look great-until you find out your metformin copay jumped from $10 to $45. Add in your other meds, and you’re paying $800 more a year. Always calculate total drug cost, not just the monthly fee.
2. The "Network Cut" Trap
Some plans have two pharmacy networks: preferred and standard. Preferred means lower cost. Standard means higher. If your pharmacy is now "standard," you’re paying more-even if you didn’t change anything.
3. The "Specialty Tier" Trap
Drugs like Ozempic, Humira, or Enbrel are often in specialty tiers. In 2025, 42% of plans increased cost-sharing on these drugs. You might pay 33% coinsurance instead of $10 copay. That’s $1,000+ extra per year.
Also, check for prior authorization or step therapy requirements. Some plans force you to try cheaper drugs first-even if your doctor says they won’t work for you. That can delay care and cause health problems.
Don’t Forget About the Inflation Reduction Act Changes
For 2026, the Inflation Reduction Act is still reshaping drug coverage. Here’s what matters:
- Insulin is capped at $35/month-no matter your plan. If your insulin costs more, switch plans or ask your pharmacy to apply the cap.
- The donut hole is gone. You no longer face a coverage gap. Once you hit your out-of-pocket limit, you pay 25% coinsurance for the rest of the year.
- Out-of-pocket cap is $2,000 for Part D. That’s the most you’ll pay for drugs in 2026. If your plan doesn’t cap costs, it’s not compliant.
These rules apply to all Part D and Medicare Advantage plans. If your plan says you’re still paying $100 for insulin, it’s wrong. Contact Medicare or your State Health Insurance Assistance Program (SHIP).
Call Your SHIP Counselor
If you’re confused, don’t guess. Every state has free, certified counselors through SHIP. In the UK, you’d go to NHS or Citizens Advice-but in the U.S., SHIP is your lifeline. They help you compare plans, read the ANOC, and even file complaints if a plan misrepresents coverage.
SHIP counselors helped 68% of callers in 2024 understand formulary changes. They’re not salespeople. They don’t get paid by plans. They just want you to get the best coverage.
To find yours, call 1-800-MEDICARE or visit medicare.gov/ship.
Final Checklist Before December 7
Here’s what to do before the deadline:
- ✅ List all your meds with dosages
- ✅ Get your current plan’s ANOC
- ✅ Use Medicare Plan Finder to compare total drug cost
- ✅ Confirm your pharmacy is preferred
- ✅ Check if your specialty drugs are capped or restricted
- ✅ Call SHIP if anything’s unclear
- ✅ Submit your new plan choice by December 7
It takes about 3.7 hours total. But the savings? On average, people who do this save $532 a year on prescriptions. Some save over $1,200.
What If You Miss the Deadline?
If you miss December 7, you’re locked in until next year-unless you qualify for a Special Enrollment Period. Those are rare. Examples: moving out of state, losing employer coverage, or your plan leaves Medicare. If you don’t qualify, you pay more for a full year.
And if you drop Part D coverage and later rejoin, you’ll pay a late enrollment penalty-1% of the national base premium for every month you were without creditable coverage. That’s permanent.
Can I switch Medicare Advantage plans after January 1?
Yes-but only once, between January 1 and March 31, during the Medicare Advantage Open Enrollment Period (MAOEP). You can switch from one Medicare Advantage plan to another, or drop it and go back to Original Medicare. But you can’t switch Part D plans during this time. If you want to change your drug coverage, you must wait until next October.
Why does my drug cost more this year even though my plan didn’t change?
Your drug’s formulary tier may have changed, even if your plan didn’t. Plans update their formularies every year. A drug that was on Tier 2 last year could move to Tier 4 this year, increasing your copay from $15 to $60. Always check the ANOC for formulary changes-not just premium changes.
Is it better to get a Medicare Advantage plan or a Part D plan?
It depends. Medicare Advantage plans bundle Parts A, B, and usually D, and include an out-of-pocket maximum (capped at $8,000 in 2025). But they have narrow networks-only 43% offer out-of-network coverage. Standalone Part D plans have broader pharmacy networks but no cap on total out-of-pocket costs. If you take multiple high-cost drugs, Advantage might be better. If you see many specialists, Original Medicare + Part D may give you more flexibility.
How do I know if my pharmacy is preferred?
When using the Medicare Plan Finder tool, enter your pharmacy’s name and zip code. It will show whether it’s "preferred" or "standard." Preferred pharmacies usually have lower copays. You can also call your pharmacy and ask if they’re in-network with your plan. Don’t assume-they change networks often.
What if my medication is removed from the formulary?
If your drug is removed, your plan must notify you 60 days before the change. You can request a formulary exception-ask your doctor to submit a letter explaining why you need it. If approved, the plan must cover it. You can also switch to a new plan during Open Enrollment that covers your drug. Don’t wait until you run out.
