Are you overwhelmed by all the TV commercials, emails, and letters telling you how to sign up for Medicare? After hearing about the various “parts” and enrollment periods, you may be wondering, “What are the biggest mistakes people make with Medicare, and how can I avoid them?”

Without a clear path to Medicare enrollment, you may:

• Miss your enrollment period: resulting in a late penalty or a lapse in coverage
• Choose the wrong plan or not have enough coverage: leading to high out-of-pocket costs
• Neglect future enrollment periods: missing the best time to adjust coverage to meet your changing health care needs

To avoid these mistakes, you need a clear understanding of the enrollment process. Let us help you cut through the noise, get answers to your questions, and learn how to sign up for the right Medicare plan for your situation, step by step.

Step 1: Know when you’re eligible for Medicare

You become eligible for Medicare on your 65th birthday. But you may be eligible at a younger age if you have a special condition, such as permanent kidney failure, Lou Gehrig’s disease, or a qualifying disability. 

While Medicare is a federal program offered through the Centers for Medicare and Medicaid Services (CMS), your enrollment is managed by the Social Security Administration (SSA). Therefore, if you’re receiving Social Security benefits or Railroad Retirement Board benefits before the age of 65, you’ll be automatically enrolled in Medicare Part A on your 65th birthday. If you’ve been receiving SSA or railroad retirement benefits for at least four months before that birthday, you’ll be automatically enrolled in Part B, too. 

When these situations don’t apply to you, you’ll need to sign up for Medicare Part A and/or Part B.

When should I sign up for Medicare?

While there are different Medicare enrollment periods, the best time to sign up is during your initial enrollment period (IEP), so you can avoid a potential fine or a lapse in health insurance.

Your IEP is seven months. It begins three months before your 65th birthday, continues through your birthday month, and ends three months after it. Enter your date of birth on the SSA website to determine your IEP.

Can I have Medicare and other insurance?

If you plan to work past 65 and have group health coverage, you can enroll in Medicare during your IEP or delay it. Compare both plans’ benefits and costs to decide.

If you keep your employer's health coverage, consider signing up for Medicare Part A if you qualify for the premium-free option. You can enroll in Part B later during a special enrollment period without penalty. This period lasts eight months after your group health coverage or employment ends.

How does Medicare work with my current health plan?

If you enroll in Medicare and keep your other health coverage, the order in which your plans are billed — known as “coordination of benefits” — will be established. That means, one insurance plan will become the “primary payer,” while the other will be the “secondary payer.” The primary payer will receive the bill first and pay benefits as contracted. If a balance remains, the secondary payer is notified and pays according to its terms.

Determine the coordination of benefits between Medicare and your current plan on the Medicare website.

Step 2: Understand your options for Medicare

Now that you’ve marked your calendar for your initial enrollment period, it’s time to determine which Medicare plan is right for you. You’ll need to understand the Medicare Parts to know which you’ll choose. 

What are the different parts of Medicare?

The ABCs of Medicare — referring to Medicare Parts A, B, and C — may be the most confusing aspect of your new health care coverage. Here is a summary of these letters/plans:

• Parts A and B make up “original Medicare,” which is offered by the federal government. 
  • Part A is hospital insurance. It provides coverage for inpatient hospital care, skilled nursing facilities, and home health care. 
  • Part B is medical insurance. It helps you pay for medically necessary physician services, preventative care, and durable medical equipment. 
• Part C refers to Medicare Advantage plans, which are sold by private insurance companies and have been approved by Medicare. These plans combine the benefits of Parts A and B (and typically Part D) into one insurance plan. They may also include benefits not provided with original Medicare, such as those for dental, hearing, and vision. 
  • Important note: To enroll in Medicare Part C, you’ll first need to sign up for Medicare Parts A and B.
• Part D is a prescription drug plan that is usually included in Medicare Advantage plans. When choosing original Medicare, you can add Part D to your health care coverage. 

You may see or hear other letters, such as Plan G or Plan N, in your research. These are not base insurance plans. They’re Medicare Supplement plans that provide extra coverage for original Medicare and are discussed in more detail below. 

What is the difference between original Medicare and Medicare Advantage?

You may have already noticed contrasts between these offerings, such as who offers them and how they’re bundled or sold. But there are other key differences to learn as you choose between original Medicare and Medicare Advantage plans. 

One is the availability of your provider network. Original Medicare is accepted by 98% of all U.S. health care providers as of 2024. Each Medicare Advantage plan will have its own network of doctors and hospitals that may not include your preferred provider(s). It’s important to check, or you may have unforeseen out-of-pocket costs. 

What is the cost for Medicare?

Whether you select original Medicare or Medicare Advantage, you’ll pay premiums, deductibles, and other out-of-pocket expenses, which will vary year to year.

For Medicare Part A:

• Premium: You likely won’t pay a monthly premium if you or your spouse worked for 10 years or more. If you’re among the minority that pay a premium, your amount will depend on your work history. 
• Deductible: You must meet a deductible each benefit period before Medicare will pay. For 2025, the deductible is $1,676. Please note that you may have multiple benefit periods in one year. 
• Other expenses: Your expenses may include a set amount each day of an extended stay in an inpatient or skilled nursing facility. You’ll also be responsible for 20% of the approved cost for durable medical equipment, among other costs.

For Medicare Part B:

• Premium: You’ll pay a premium each month. The amount is based on your income. For example, in 2025, the monthly premium is $185 for those with gross incomes of $106,000 or less. Your premium may be higher if you have a high income. 
• Deductible: You’ll also need to meet a deductible once each year before Medicare pays. The 2025 amount is $257. 
• Coinsurance: After the deductible is met, you’ll have a 20% coinsurance payment on services and products covered under Part B. This is assuming your provider accepts and bills the Medicare-approved amount. Otherwise, your out-of-pocket amount may be greater.
• Other expenses: You must also pay 20% of the Medicare-approved amount for durable medical equipment and doctors’ services. These may be provided during an inpatient hospital stay, as part of outpatient hospital care, or for outpatient mental health care. You may also have other copayments or out-of-pocket costs.

For Medicare Advantage (Part C):

• Premium: You must pay your Part B premium as well as any premium the private insurance company charges for Part C. 
• Other costs: Your out-of-pocket maximum will depend on your specific plan.

You may also have other monthly costs for:

• Part D premium: varies based on your income
• Late enrollment penalties: For example, Part B may carry an extra 10% charge for each year you didn’t sign up for it when you were eligible.
• Supplemental insurance premiums: Medicare Supplement, Hospital Indemnity, Critical Illness, Dental, Short-term Care insurance, and more

Step 3: Gather required information and documents

As you prepare to enroll for Medicare, your next step is to ensure you have all the information that the SSA requires to sign up. This includes:

• Your Social Security number
• Your place of birth
• Health insurance information, including start and end dates for current group health plans

Other information may be necessary based on your situation. For example, if you’re already enrolled in Part A and are now enrolling in Part B, you’ll need your Medicare number. You must also fill out a specific form in this situation or others that require you to enroll outside your IEP, such as in a special enrollment period or general enrollment period. If this applies to you, you can download the form you need on the Medicare website.

Step 4: Sign up for Medicare during your initial enrollment period

When your IEP begins, you have options for signing up for your Medicare coverage with the Social Security Administration. You can enroll online on the SSA website, apply by phone, or visit a SSA office. 

Please note, if you or your spouse worked for a railroad, you’ll need to call the Railroad Retirement Board about your Medicare enrollment. The number is 877-772-5772.

How can I sign up for Medicare online?

As a first-time enrollee, visit the SSA website and click “Sign up for Medicare”. Each page provides easy-to-follow instructions. You may even choose to save your application and come back later to complete it, if needed.

Again, if you wish to have a Medicare Advantage plan for your health care coverage, you’ll still need to enroll in original Medicare first. After you’ve done so, you may review the Medicare Advantage and prescription drug plans available in your area on Medicare’s website. You’ll need to have your Medicare number before you can enroll.

Who do I talk to about getting Medicare?

If you prefer to enroll in Medicare by phone, you do have that option. Whether you speak English, Spanish, or another language, call 800-772-1213. The TTY number is 800-325-0778. You’ll need to know which part(s) you’re signing up for — Parts A and B or Part A only — before calling.

You may also visit your closest SSA office to apply for Medicare. You may wish to schedule an appointment to save time.

How will I know my Medicare enrollment has been approved?

You’ll receive a welcome package from Medicare that contains your Medicare card and a booklet with information on your new health care plan. It generally arrives two weeks after you sign up. This is also true for those who are automatically enrolled based on having a disability or receiving SSA benefits.

Step 5: Fill gaps in your Medicare coverage

Many older adults think original Medicare or Medicare Advantage plans will cover all their health care costs, but that's not always the case. Luckily, you have options for supplemental health coverage to fill gaps and protect your health and finances. 

What supplemental coverage is available for original Medicare?

To get more complete health care coverage, consider adding these options to your original Medicare plan:

Medicare Supplement insurance 

Also referred to as “Medigap,” these plans help cover deductibles, copayments, coinsurance, Part B excess charges, or even foreign travel emergencies, if you plan to travel in retirement. The specific benefits vary depending on which of the 10 standardized plans you decide is right for you. For more coverage, look for a Medicare Supplement plan with a Dental rider that allows you to stay with your existing dentist.

The best enrollment period for Medicare Supplement plans is the six months following your 65th birthday. It’s this time when you aren’t required to answer questions about your health and can secure the best rate.

Dental insurance 

Dental insurance is important when a Dental rider is not available in your state or when you want more coverage. Having dental care is important since poor oral health increases your risk of certain cancers and Alzheimer’s disease. 

What supplemental coverage is available for Medicare Advantage?

You cannot legally pair Medicare Supplement plans with Medicare Advantage, but you may seek other ways to protect your retirement savings:

Hospital Indemnity insurance 

This option can reduce your out-of-pocket costs when you have a hospital stay. It pays you the cash benefit amount you choose during enrollment each day of your hospital stay, allowing you to use that money as needed. For added flexibility, most Hospital Indemnity insurance has no deductible and doesn’t require pre-certification. You can also add optional rider benefits for ambulance services, cancer diagnoses, and skilled nursing services, among other needs.

What supplemental coverage pairs well with original Medicare or Medicare Advantage?

Critical Illness insurance 

Critical Illness insurance empowers you to build the coverage you need and to focus on what matters when illness strikes. Depending on the policy, you can cover cancer, heart attack, stroke, or more. You indicate on your policy the lump sum benefit amount that you’ll be paid directly if you receive a qualifying diagnosis.

Short-term Care insurance 

Unless you have significant savings to cover extended care, Short-term Care insurance becomes a must-have as you age. When you turn 65, you have a 70% risk of needing long-term care, which Medicare Advantage and Medicare don’t cover. Short-term Care insurance pays a cash benefit each day of your stay in a skilled nursing facility or for home health care needs up to 360 days. Short-term Care insurance can bridge the gap while you wait for Long-term Care insurance to kick in. It's easier to qualify for and is usually less expensive.

Step 6: Review your health status and needs annually.

Each year, it’s important that you evaluate your insurance coverage during Medicare’s open enrollment period, which runs Oct. 15 to Dec. 7. 

Do you need a plan that includes your preferred providers in its network? Did you lose benefits and need supplemental coverage? If the insurance you have doesn’t meet your current or potential health care needs, both your physical and financial status may be at risk. Fortunately, you can switch insurance plans to help ensure your continued well-being.

Learn more

Wellabe can help you fill coverage gaps with supplemental insurance plans:

• Visit the products page to see what is available in your state
• Call 877-257-2663 to speak to an agent
• Request a personalized, free quote

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