7 Medicare Open Enrollment Errors That Could Raise Retirees’ 2027 Costs

Your Medicare plan may have served you well this year, but that does not mean it will be the best choice for next year. Retirees who ignore changes to prescription coverage, provider networks, and out-of-pocket costs could end up paying more even if their monthly premium stays unchanged. With Open Enrollment underway, beneficiaries have a chance to review their options before those changes kick in.

The average Medicare Advantage premium is expected to fall, but individual plans can still shift in price and benefits. Steering clear of these seven Open Enrollment mistakes may help retirees protect their savings and avoid costly surprises when they need care.

1. Assuming the Current Plan Will Not Change

One of the most common mistakes is renewing coverage without checking what is different. Each fall, Medicare Advantage and Part D plans mail an Annual Notice of Change that lays out updates to premiums, deductibles, benefits, and other coverage details.

Beneficiaries should review that notice before deciding on coverage for the coming year. A plan that made prescriptions affordable one year may include different copayments or restrictions the next, even if the plan name remains the same. Spending a few minutes comparing the notice with current benefits can prevent unwelcome surprises.

2. Picking a Plan Only Because the Monthly Premium Is Low

A Medicare Advantage plan with a $0 monthly premium can seem appealing, especially for someone on a fixed income. But that figure does not replace the Medicare Part B premium, and it does not guarantee low overall medical spending. Depending on the plan, members may still face deductibles, specialist copays, hospital charges, and other out-of-pocket costs.

For instance, saving a modest amount each month on premiums may look worthwhile until several specialist visits or a hospital stay erase the savings. Comparing estimated total costs through Medicare’s Plan Finder is a better approach than choosing coverage based on one attractive price tag.

3. Failing to Verify Prescription Coverage

Prescription drug coverage deserves close attention because Part D costs are changing again. The maximum annual deductible is increasing, and the yearly out-of-pocket threshold for covered Part D drugs is also rising.

Even so, that threshold does not mean every beneficiary will spend that amount, and premiums or excluded drugs can add more costs. Plans can also adjust formularies, preferred pharmacies, drug tiers, and review requirements, which may affect medications you have relied on for years. Before renewing, enter your full medication list, dosages, and preferred pharmacy into Medicare’s comparison tool to estimate likely costs.

4. Not Checking Whether Doctors Remain In-Network

Keeping your doctors can matter just as much as finding a low premium. Medicare Advantage plans often use provider networks, and participating physicians, hospitals, and specialists can change from year to year. The Medicare Rights Center recommends confirming whether your providers and pharmacies will still be in-network before selecting coverage.

It can be frustrating to learn after the new year begins that a longtime cardiologist no longer participates in your plan, leaving you to switch doctors or pay more, depending on your coverage. Contact the insurer and your doctor’s office to confirm participation in the exact plan you are considering.

5. Leaving Original Medicare Without Understanding Medigap Rules

Another expensive mistake is moving from Original Medicare with Medigap into Medicare Advantage without thinking through the long-term effect. Medicare Advantage may offer extra benefits and lower advertised premiums, but switching back later does not always mean you can buy the same Medigap policy again. After leaving Medigap, beneficiaries may face limits when trying to re-enroll. Outside certain guaranteed-issue rights and state protections, insurers may use medical underwriting or deny applications based on health history.

Before making the change, check your state’s Medigap rules and understand what options would remain if your health needs changed later.

6. Ignoring Free Help That Could Reduce Costs

Many retirees spend hours comparing plans without realizing that free, personalized guidance is available. State Health Insurance Assistance Programs, or SHIPs, offer unbiased Medicare counseling to help beneficiaries understand coverage choices, enrollment rules, and possible financial assistance.

Counselors can also help determine whether someone qualifies for programs such as Medicare Savings Programs or Part D Extra Help, which can lower certain costs for eligible people. A retiree struggling with prescription expenses may find that an assistance program makes a meaningful difference in the monthly budget.

Visit SHIP’s national website or call 1-800-MEDICARE to find dependable guidance before choosing coverage.

7. Waiting Too Long and Missing the Enrollment Deadline

One of the most frustrating mistakes is finding a better plan but failing to enroll in time. The annual Open Enrollment Period runs from October 15 through December 7, with coverage changes generally taking effect at the start of the next year. During this window, beneficiaries can switch Medicare Advantage plans, change Part D plans, or move between Original Medicare and Medicare Advantage, subject to the applicable rules.

Medicare Advantage members also have a separate enrollment window early in the year, but that period has narrower rules and is not a universal second chance for everyone. Waiting until the last minute to compare plans, contact insurers, or submit paperwork increases the chance of missing an opportunity to improve coverage.

A Small Amount of Research Now Can Protect Next Year’s Budget

Open Enrollment is more than a yearly paperwork task; it is a chance to make sure your health coverage still fits your medical needs and financial situation. The cheapest plan is not always the most affordable, and keeping the same coverage without checking for changes can lead to unexpected costs. Begin with your Annual Notice of Change, then compare prescriptions, provider networks, deductibles, premiums, and possible out-of-pocket expenses for the coming year. If you are unsure which option is best, use Medicare’s official comparison tools or speak with a SHIP counselor before the deadline. Avoiding these Open Enrollment mistakes could help you enter the next year with more confidence and less pressure on your retirement savings.