Medicare Annual Review: How to Check Your Parent's Plan Every Year

Most families go through the intense work of helping a parent enroll in Medicare at 65 — and then assume the job is done. It isn't. Medicare is not a "set it and forget it" system. Plans change their premiums, drug formularies, and provider networks every single year. A plan that was the right choice in 2024 may cost your parent hundreds of dollars more in 2026 for the exact same medications.

That annual review window is called the Annual Open Enrollment Period (OEP), and it runs October 15 through December 7 every year. If you're an adult child helping manage a parent's healthcare, blocking time every fall to audit their coverage is one of the highest-value things you can do for their financial wellbeing.

Here's how to do it properly.

Why Medicare Plans Change Every Year

Private Medicare plans — both Medicare Advantage (Part C) and Part D prescription drug plans — are approved and repriced by CMS every calendar year. Insurance companies submit new bids annually. That means:

• Premiums can increase even if your parent's health hasn't changed
• Drug formularies change — a medication that was Tier 2 (generic copay) can move to Tier 4 (specialty cost-sharing) without warning
• Networks shrink — doctors and hospitals can drop out of a plan's network
• Star ratings shift — a plan with 4 stars this year may drop to 3 stars next year as quality metrics change

Medicare sends every beneficiary an "Annual Notice of Change" (ANOC) letter by September 30 each year. This document spells out exactly what's changing in their current plan. Most seniors either don't read it or don't know what to do with it. That's where you come in.

Step 1: Find the Annual Notice of Change Letter

Look for the ANOC letter in your parent's mail in late September. If they've moved, opted out of paper mail, or if it got lost, you can also log into their MyMedicare.gov account to review plan information digitally.

The ANOC tells you:

• New monthly premium for their plan
• Changes to cost-sharing (deductibles, copays, coinsurance)
• Network or formulary changes

Even if the letter says nothing major changed, you still need to do Step 2 — because the competitive landscape changes, meaning a better plan may now be available even if their current one is the same.

Step 2: Pull the Current Medication List

Before you can compare plans objectively, you need an accurate, current list of every medication your parent takes. Get the exact:

• Drug name (brand and generic)
• Dosage (10mg vs. 20mg can price differently)
• Frequency (once daily vs. twice daily)
• Which pharmacy they use

This is the data the Medicare Plan Finder tool needs to give you meaningful comparisons.

Step 3: Run the Medicare Plan Finder

Go to medicare.gov/plan-compare and log in using your parent's MyMedicare.gov credentials. Logging in (rather than using as a guest) allows the tool to pull their actual claims history automatically, ensuring their drug list is complete.

Enter the medication list and select their preferred pharmacy. The tool will generate every available plan in their zip code and calculate an estimated Total Annual Drug + Premium Cost for each one.

Sort by "Lowest Drug + Premium Cost." This is the number that matters — not the monthly premium alone. A plan with a $0 premium but poor formulary placement for your parent's specific drugs can cost far more than a plan with a $40/month premium.

Step 4: Check the Provider Network (for Medicare Advantage Plans)

If your parent is in a Medicare Advantage plan, verify that their doctors are still in-network. Use the plan's online directory or call the plan directly. Do not assume last year's network still applies — contracts between insurers and providers are renegotiated annually.

Losing access to a specialist your parent has been seeing for years is a significant disruption. If their primary care doctor or a key specialist has dropped out of the network, that alone may justify switching plans.

Step 5: Check the Plan's Star Rating

CMS publishes updated star ratings every fall. You can see these on the Medicare Plan Finder. A plan with fewer than 3.5 stars should raise concern — it means CMS has found deficiencies in quality metrics, appeals handling, or customer service.

A plan with 5 stars earns a special benefit: beneficiaries can switch to it at any time of year (not just during OEP). If a 5-star plan is available in your parent's area, it's worth serious consideration.

Step 6: Make the Change (if needed)

If you find a better plan, switching during the Annual OEP (October 15 – December 7) is straightforward:

• For Part D plans: Enroll in the new plan directly at medicare.gov or by calling the plan. The old plan is automatically cancelled when the new one begins January 1.
• For Medicare Advantage plans: Enroll in the new plan. The old plan cancels automatically.
• For switching from Medicare Advantage back to Original Medicare: You can do this during OEP, but be aware you may not have Guaranteed Issue rights for Medigap at this point (unless your state has a Birthday Rule or other consumer protections). This is a significant decision worth thinking through carefully.

Changes made during OEP take effect January 1 of the following year.

The Medicare Advantage Open Enrollment Period (January–March)

If your parent made a change during the fall OEP and realized in January it was the wrong call — their doctor isn't in-network, the copays are higher than expected — there's a safety valve. The Medicare Advantage Open Enrollment Period runs January 1 through March 31.

During this window, beneficiaries enrolled in Medicare Advantage can:

• Switch to a different Medicare Advantage plan
• Drop Medicare Advantage and return to Original Medicare (and then pick a standalone Part D plan)

They cannot use this window to switch from Original Medicare to Medicare Advantage. That's specifically for OEP in the fall.

What Happens If You Don't Review

The default outcome if you do nothing: your parent stays in their current plan with whatever changes the insurer has made. In many cases this is fine. But in some years — particularly when a specific medication moves to a higher formulary tier, or when a plan loses a key provider network contract — the cost of inaction can be $500, $1,000, or more per year.

Given that this review process takes two to three focused hours once a year, the return on time is extremely high.

A Simple Annual Calendar

• September 30: ANOC letters arrive. File them, don't throw them away.
• Early October: Run Plan Finder. Check network and formulary.
• October 15 – December 7: OEP window. Make changes if needed.
• January 1: New plan year begins.
• January 1 – March 31: MA-OEP safety valve if adjustments are needed.

Getting More Help

If the comparison feels overwhelming, a few free resources can help:

• SHIP (State Health Insurance Assistance Program): Free, unbiased counseling from trained volunteers. Find your local SHIP at shiphelp.org. Contact them in early October — they get booked quickly once OEP starts.
• Medicare Rights Center: Offers a helpline (800-333-4114) for questions about specific coverage situations.

For families who want a comprehensive framework for all of Medicare — not just the annual review piece — our Medicare Enrollment Guide walks through every enrollment window, the Original Medicare vs. Medicare Advantage decision, Medigap strategies, and how to compare Part D plans step by step.

Annual Medicare review isn't glamorous work, but it's one of the most concrete ways you can protect your parent's financial stability as a caregiver. Set the calendar reminder now for October 1.