How to Plan Annual Open Enrollment for Medication Coverage in Medicare

Every year, millions of Medicare beneficiaries miss out on hundreds - sometimes over a thousand - dollars in savings just because they don’t review their prescription drug coverage. It’s not that they don’t care. It’s that they don’t know where to start. If you take one or more medications regularly, skipping your Annual Open Enrollment Period (AEP) could cost you more than your monthly premium. The window to change your coverage is short: October 15 to December 7 each year. Changes take effect January 1. If you wait until January, it’s too late - unless you qualify for a special enrollment period, which most people don’t.

Know What’s Changing - Your Medications Might Not Be Covered the Same Way

Plans change every year. Not just premiums. Not just networks. But the drugs you rely on. A medication that was on Tier 2 last year - meaning you paid $15 a month - could jump to Tier 4 this year, costing you $85. That’s not a rumor. It’s standard practice. According to CMS, about 60% of Part D plans change at least one drug’s formulary status annually. Insulin, GLP-1 drugs like Ozempic, and heart medications are the most common culprits. One beneficiary in Edmonton switched plans in 2025 after discovering his blood pressure med moved from Tier 2 to Tier 5. His monthly cost went from $28 to $142. He saved $1,368 a year by switching.

Don’t assume your current plan still works. Even if you’ve been with the same insurer for five years, your coverage could be completely different this year. The first thing you need is your Annual Notice of Change (ANOC). It arrives in the mail between October 1 and October 15. Read it. Highlight every medication you take. Note any changes in tier, prior authorization rules, or quantity limits. If your plan says “no changes,” don’t believe it. Cross-check with the Medicare Plan Finder tool.

Use the Medicare Plan Finder - But Don’t Just Look at Premiums

The Medicare Plan Finder on Medicare.gov is your most powerful tool. It’s free, official, and updated daily. But most people use it wrong. They sort by lowest monthly premium. Big mistake. A $0 premium plan might charge $500 out-of-pocket for your top three meds. A $40 plan might cover them for $10 each.

Here’s how to use it right:

1. Enter your full name, zip code, and date of birth.
2. Under “Drugs,” type in every medication you take - including dosage and frequency. Don’t skip generics or over-the-counter drugs your doctor prescribed.
3. Click “Compare Plans.”
4. Look at the “Estimated Annual Drug Cost” column - not the monthly premium.

This number includes your deductible, copays, and what you pay in the coverage gap. For 2026, the Part D deductible is capped at $590. The out-of-pocket maximum for Medicare Advantage plans is $8,000. But if you’re on Original Medicare with a standalone Part D plan, there’s no cap - you could pay more if your drugs are expensive.

Also check if your pharmacy is preferred. Some plans charge double if you fill prescriptions at a non-preferred pharmacy. If you use Shoppers Drug Mart or a local independent pharmacy, make sure it’s in-network. One user in Calgary switched plans only to find his local pharmacy was no longer covered. He had to drive 45 minutes to fill his scripts.

Understand Formulary Tiers and Restrictions

Medicare drug plans group medications into tiers. The lower the tier, the less you pay:

• Tier 1: Generic drugs - usually $5-$15
• Tier 2: Preferred brand-name drugs - $20-$50
• Tier 3: Non-preferred brand-name drugs - $50-$100
• Tier 4: Specialty drugs - $100-$500+ (like Ozempic, Humira, or cancer drugs)

Some plans put drugs on “specialty tier” even if they’re not technically expensive. That’s where you get hit hardest. In 2024, 42% of plans increased cost-sharing for specialty tier drugs. If you take one of those, you need a plan that covers it at Tier 2 or lower.

Watch for restrictions too. Some plans require you to try a cheaper drug first (step therapy). Others limit how many pills you can get per month (quantity limits). A few require your doctor to call in prior authorization just to fill your script. That delays care. And if your doctor doesn’t know the rules, you might show up at the pharmacy and get turned away.

Medicare Advantage vs. Original Medicare + Part D

Most people don’t realize Medicare Advantage (Part C) plans bundle Parts A, B, and usually D. That sounds convenient - but it’s not always better.

Here’s the trade-off:

Medicare Advantage vs. Original Medicare with Part D

Feature	Medicare Advantage (Part C)	Original Medicare + Standalone Part D
Drug Coverage	Usually included (90% of plans in 2025)	Must enroll separately in Part D
Out-of-Pocket Max	Capped at $8,000 in 2025	No cap - could pay thousands more
Provider Network	Restricted - only in-network doctors	Any doctor who accepts Medicare
Pharmacy Network	Often limited - check preferred pharmacies	Broader access - most pharmacies accept Part D
Annual Switches	Only one change allowed Jan 1-Mar 31	Can change Part D anytime during AEP

If you take multiple specialty drugs and want protection from huge bills, Medicare Advantage might be worth it. But if you see specialists outside your area, travel often, or use a pharmacy that’s not in-network, Original Medicare with a standalone Part D plan gives you more flexibility.

Don’t Forget the Inflation Reduction Act Changes for 2026

The Inflation Reduction Act changed everything for medication costs. Starting January 1, 2026:

• Insulin costs are capped at $35 per month - no matter what plan you’re on.
• The Part D coverage gap (donut hole) is fully closed. You pay 25% for all brand-name drugs, even in the gap.
• Some high-cost drugs (like those over $100/month) may have additional manufacturer discounts.

These rules apply to every Part D plan. So even if your plan changes, your insulin cost won’t go up. But that doesn’t mean you shouldn’t shop around. The cap only helps with insulin. If you take five other medications, you still need to compare formularies. And if you’re on a Medicare Advantage plan, make sure those caps are applied correctly. Some plans still try to charge more.

Five Steps to Get It Right - No Guesswork

Follow this simple timeline. It takes about 3-4 hours total. But it could save you $1,000+ a year.

1. October 1-10: List your meds - Write down every drug, dose, and how often you take it. Include vitamins or supplements your doctor told you to take.
2. October 10-15: Get your ANOC and EOC - Your current plan sends these. Read them. Circle every change.
3. October 15-20: Use Medicare Plan Finder - Enter all your drugs. Sort by “Estimated Annual Drug Cost.”
4. October 20-25: Check your pharmacy - Confirm your local pharmacy is preferred. Call them if unsure.
5. October 25-December 7: Enroll - Don’t wait. If you miss December 7, you’re stuck until next year.

Most people don’t do this alone. About 68% of beneficiaries need help. That’s where SHIP - State Health Insurance Assistance Programs - comes in. Free, local, trained counselors. In Edmonton, you can call 1-800-567-2277 or visit your local community health center. They’ll walk you through the Plan Finder. No charge. No sales pitch.

What Happens If You Do Nothing?

If you don’t make a change, you’ll automatically be re-enrolled in your current plan. Sounds safe. But here’s what usually happens:

• Your premium goes up - often by 10-20%.
• Your drug moves to a higher tier - your copay jumps.
• Your pharmacy is no longer preferred - you pay more to fill scripts.
• A drug you take gets removed from the formulary - you can’t fill it at all.

One woman in Winnipeg stayed in her plan because she “didn’t want to deal with it.” Her GLP-1 drug was removed from the formulary in January. She paid $1,100 out of pocket for a single month’s supply. She had to switch to a cheaper alternative - which didn’t work as well. She lost weight. Her blood sugar spiked. Her doctor had to adjust her treatment plan.

You don’t have to be perfect. You just have to act. One review. One comparison. One enrollment. That’s all it takes to avoid a financial or health setback.

If you take medications regularly, your annual enrollment isn’t just paperwork - it’s your best chance to control your health costs. Don’t treat it like a chore. Treat it like a checkup. Just like you see your doctor once a year, check your coverage. You’ll save money. You’ll avoid surprises. And you’ll make sure your prescriptions are covered - exactly when you need them.