3 Mistakes People Make When Choosing a Medicare Plan

Navigating Medicare plan options can feel overwhelming, especially when coverage rules aren’t easy to understand. It’s common for people to make avoidable mistakes that impact costs, coverage, or provider access. Because Medicare plans are not one-size-fits-all, it’s important to review your coverage and make sure your plan fits your health, lifestyle, and budget. With that said, you'll want to avoid the three most common Medicare mistakes when choosing you coverage.

Mistake #1. Missing Important Medicare Enrollment Deadlines

One of the most costly Medicare mistakes is missing key enrollment deadlines and ending up with lifelong penalties. Many people don’t realize how strict Medicare’s timing rules are until it’s too late.

IEP - Initial Enrollment Period

When you first become eligible for Medicare, you have a 7-month Initial Enrollment Period around your 65th birthday to enroll in Medicare Parts A and B. If you miss this window and don’t have qualifying coverage, you may have to wait until the General Enrollment Period (January 1 – March 31) to enroll. Delaying Part B can result in a penalty that increases your monthly premium by 10% for every full 12 months you wait, and that penalty typically lasts for life.

Part D Late Enrollment Penalty

Prescription drug coverage is another area where people commonly get tripped up. When you enroll in Medicare Parts A and B, you also become eligible for Part D prescription drug coverage. Even if you don’t currently take medications, delaying Part D without other creditable drug coverage can trigger the Part D Late Enrollment Penalty if you enroll later. The longer the delay, the higher the penalty.

Because of this, many people choose to set up prescription coverage early, even if it’s low cost, just to avoid future penalties. Some Medicare Advantage plans often include prescription drug coverage at no additional cost, which can also help prevent this issue.

Understanding and preparing for these enrollment deadlines can save you from unnecessary costs and frustration down the road.

👉 Tip: Use our Free Medicare Checklist to make sure you know your enrollment windows and don't set yourself up with lifelong penalties.

Mistake #2. Assuming Original Medicare Covers Everything

Another common mistake seniors make is just assuming "Medicare covers everything" and enrolling in Parts A and B without adding any additional coverage. While Original Medicare provides a strong foundation, it does not cover all healthcare costs, and those gaps can add up quickly.

Many people are surprised to learn that Original Medicare typically leaves you responsible for 20% coinsurance on most medical services, along with deductibles (which you may have to pay multiple times in a year) and no annual out-of-pocket maximum. This means there is no cap on what you could pay in a year if you need frequent or expensive care.

Additional Coverage

To help manage these costs, many people choose to add a Medicare Supplemental Plan (Medigap) which is designed specifically to "cover the gaps" in coverage that original Medicare leaves. Another option is to add a Medicare Advantage Plan which can offer low monthly premiums, as low as $0 and uses a pay as you go structure for managed care. These plans can also include added benefits such as dental, vision, hearing, and fitness memberships which is not included in original Medicare.

Because everyone’s health and financial situations are unique, it’s important to understand how Original Medicare works and explore your options before deciding on coverage. Making assumptions at this stage can leave you exposed to costs you weren’t expecting.

👉 Tip: Consider adding ancillary products such as a hospital indemnity or a cancer, heart attack, and stroke plan in addition to your medicare coverage for added protection.

Mistake #3. Not Understanding Doctor and Hospital Networks

This mistake often happens when someone enrolls in a Medicare Advantage plan without fully understanding how provider networks work. While Medicare Advantage plans can offer low-$0 monthly premiums and added benefits, they also come with network rules that can directly affect where and how you receive care.

HMO Plans

Some plans, especially HMO options, require you to use doctors and hospitals within a specific network and may require referrals from a primary care physician before seeing specialists or receiving care. If your doctors are not in the plan’s network, you could face higher costs or be subject to paying their out-of-pocket rates.

PPO Plans

For people who want more flexibility, PPO plans may offer broader access to providers and no referral requirements, which can be helpful for those who travel or prefer more choice. However, the provider must still agree to treat you and you may have to pay more to use providers or services outside of the plans network.

Yearly Network Changes

Another factor many people overlook is that doctor and hospital networks can change from year to year. Provider participation varies by plan, not just by insurance company. A provider that accepts your plan today may not accept it next year, which is why reviewing your coverage regularly and confirming your providers is so important.

Understanding network rules before enrolling can help you avoid disruptions in care and unexpected out-of-pocket costs.

👉 Tip: During the Annual Enrollment Period (Oct 15–Dec 7), always check your plans provider network and any formulary drug changes.

Next Steps

Medicare decisions don’t have to be overwhelming especially with the right guidance. Understanding these common mistakes can help you avoid unexpected costs, coverage gaps, and disruptions in care. Taking time to review your options and ask the right questions can go a long way toward choosing coverage that truly fits your needs and preserving your peace of mind knowing you are covered the way you should be.