Five Expensive Medicare Mistakes and How to Avoid Them
The five most expensive Medicare mistakes — and how to avoid every one.
5 min read · Last reviewed October 15, 2026
Key takeaways
- Most expensive Medicare mistakes are timing mistakes, and timing mistakes can be permanent.
- The plan with the lowest premium is frequently not the plan with the lowest total cost.
- A yearly review during the fall election period catches most problems before they cost you.
1. Missing your Initial Enrollment Period
Your IEP is the seven months around your 65th birthday. If you are not automatically enrolled and you miss it without qualifying for a special window, you may have to wait for the General Enrollment Period, go months without coverage, and pay a Part B penalty for life. Mark the start of your IEP on the calendar the year you turn 64.
2. Delaying Part B because of the wrong kind of coverage
Delaying Part B can be a sound choice if you have active coverage through your own or your spouse's current employer. It is a costly mistake if your coverage is COBRA, retiree coverage, or an individual marketplace plan, because those do not count. People in that situation end up with a penalty and a coverage gap. Before you delay anything, confirm with Social Security and your benefits administrator that your situation qualifies.
3. Skipping drug coverage because you take nothing today
Going 63 days or more without creditable drug coverage after you are eligible triggers a Part D penalty that follows you for as long as you have Part D. The penalty grows with every month you wait. A low-cost drug plan now protects you from that penalty, and from the cost of a prescription you do not see coming.
4. Ignoring the Annual Notice of Change
Every fall your plan mails an Annual Notice of Change listing what is different next year: premiums, copays, the formulary, the provider network, and extra benefits. Many people never open it. Then in January a doctor is out of network or a medication moved to a higher tier. Read it, or let us read it with you, before December 7 while you can still switch.
5. Choosing a plan on premium alone
A premium is one line in the total cost of a plan. The others are your deductible, your copays for the doctors you actually see, what your specific drugs cost at your pharmacy, and the out-of-pocket maximum that protects you in a bad year. A plan with a higher premium can easily cost less over twelve months. Compare the total, using your own doctors and medications.
The simple habit that prevents all five
Review your coverage once a year, every fall, with your current doctor list and medication list in hand. It takes about thirty minutes. We do these reviews at no charge, comparing plans from the carriers we represent, and we will tell you plainly if staying put is the right call.
This article is general education, not advice about a specific plan, and it is not a complete description of benefits. Premiums, deductibles, and limits are set by Medicare each year; current figures are at Medicare.gov or 1-800-MEDICARE. Plan availability varies by location.
Questions about your own situation?
A licensed agent can walk through this with your doctors and medications in hand. No cost, no pressure.