Is Medicare Mandatory? How to Avoid Lifelong Late Enrollment Penalties

Last updated September 22, 2026

Naming note: On September 3, 2026, CMS and the SBA renamed ICHRA to CHOICE Arrangement (Custom Health Option and Individual Care Expense).

If you’re in your early 60s, you’re probably starting to hear a lot about signing up for Medicare. You might be wondering if Medicare is required, and you might have questions about your options. This guide covers when Medicare is strictly required and when you could choose to delay, which parts are optional and which are mandatory, how the late enrollment penalties work, what changes if you’re still working at 65, and the five enrollment mistakes that cost people the most.

When is Medicare mandatory?

Medicare payroll taxes have been mandatory for state and local government employees hired after March 31, 1986. Enrolling in Medicare itself, though, is optional for most people, unless you receive Social Security benefits.

Which Medicare Parts are mandatory?

If you receive Social Security benefits, you’re required to enroll in Part A. If you don’t enroll, you’ll no longer receive Social Security payments. Part A covers inpatient hospital care, and it’s premium-free for individuals who have paid Medicare taxes for at least 10 years (or 40 quarters).

If you’re not getting Social Security benefits yet, Part A is not yet mandatory for you. You might choose to delay signing up for Part A in certain situations.

Medicare Part B is medical insurance that covers primary care, laboratory tests, and any care that you receive as an outpatient. It also pays for certain medical devices, including mobility aids. Part B is technically optional, but if you do not have creditable coverage in its place, you may end up paying penalties later on.

What Parts of Medicare are optional?

Medicare Part C (Medicare Advantage) is an optional replacement for Parts A and B. This Part is administered by private insurance companies and often provides extra coverage alongside the basic Medicare coverage. For instance, many Part C plans offer dental and vision coverage while some provide coverage for prescriptions and hearing aids. You may even find Part C plans that cover fitness benefits, transportation to doctor’s appointments, and home meal delivery after being discharged from the hospital.

Part D is another Part of Medicare that is not mandatory, but it may result in late enrollment penalties. This Part provides coverage for prescription drug costs and can provide important savings and capabilities. For instance, you can choose to have your prescriptions delivered through the mail-order pharmacy option, and you might be able to get a three-month supply of your medicine.

Why would I delay Medicare?

If you’re working at age 65 or above, you may be able to get health insurance through your employer. While you may be happy with this coverage, we recommend you still explore your Medicare options. Medicare can work with your existing health insurance to save you even more money. However, discuss this with your current carrier to be sure.

Likewise, you may be interested in delaying Medicare because you are contributing to a Health Savings Account (HSA). Once you enroll in Part A, you can’t contribute to a Health Savings Account anymore, but you can continue to use those funds for any qualifying health costs. It may be well worth it to switch to Medicare as soon as you’re eligible and use your HSA funds for copays, coinsurance, and deductibles.

Lastly, you might be tempted to delay Medicare enrollment because you don’t want to pay the premiums. However, be aware that if you delay your enrollment, you might be penalized with late fees that could increase your premiums when you do eventually sign up.

What are the penalties for late Medicare enrollment?

If you decline or delay Medicare, you could face late fees and other penalties. In order to avoid these penalties, you’ll need to be able to prove you had creditable coverage during the time you delayed. People who delay Medicare because of existing coverage through an employer won’t normally face any penalties or late fees when they sign up.

Otherwise, the exact penalties that you’ll face depend on your situation:

Part A

If you haven’t worked long enough to qualify for premium-free Medicare Part A, you’ll need to pay a penalty of up to 10% on the standard monthly premium after you sign up. You’ll have to pay the penalty for twice the length of time that you declined Part A. For example, if you declined Part A for two years, you’ll pay the penalty for four years.

If you get Medicare Part A premium-free, you won’t pay a penalty for late enrollment.

Part B

Part B penalties for late enrollment are up to 10% of the standard monthly premium for each 12-month period that you declined or delayed enrollment. You’ll have to pay Part B penalties for as long as you’re enrolled in Part B. If you delayed enrollment in Part B by one year, your penalty will be 10%. If you delayed by two years, a penalty of up to 20% could be added to your Part B premium for the rest of your enrollment in Part B. Delay for three years (36 months), and your penalty would be 30% of the current Part B premium.

The Part B penalty can significantly impact your healthcare costs. Not only will you have to pay the penalty on top of your monthly premium, but the penalty amount can increase each year due to annual premium adjustments. This can result in higher overall healthcare expenses and may make it more challenging to afford necessary medical care. Additionally, the penalty does not count towards your out-of-pocket spending limits, potentially leaving you with higher healthcare costs overall.

If you can prove that you had creditable coverage while you delayed enrollment, you can typically avoid this penalty. The section on working past 65 below explains how.

Part C

Part C doesn’t have its own specific penalties. However, since Part C plans include coverage for Parts A and B, you’ll still be charged penalties for late enrollment in Part A and Part B.

Part D

If you sign up for Part D after your Initial Enrollment Period (IEP), you’ll be required to pay a penalty for the entire time that you’re enrolled in Part D.

To calculate the penalty, you’ll need to know the national base beneficiary premium for the year. In 2026, the premium is $38.99. Take 1% of that figure, multiply it by the number of full months you went without Part D or other creditable drug coverage, and round to the nearest $0.10. That amount is added to your Part D premium each month. If you do not pay the premium and the penalty, your prescription coverage could be dropped.

Working past 65? What you need to know about the Part B penalty

As you approach the age of 65, you may be considering whether to delay your Medicare enrollment, specifically Medicare Part B. While there may be valid reasons for delaying enrollment, it’s essential to be aware of the potential Medicare Part B penalty described above, and to understand when it does and does not apply.

Understanding Medicare Part B While Working

Medicare Part B provides medical insurance coverage, including doctor visits, outpatient services, preventive care, and medical supplies. It is a critical component of Medicare. If you’re already receiving Social Security benefits when you turn 65, enrollment in Parts A and B is automatic. If not, you need to sign up yourself. Either way, if you plan to delay your enrollment, it’s vital to understand the potential penalties.

If you decide to delay Medicare Part B enrollment and do not have creditable coverage (employer-provided coverage that is deemed as good as Medicare’s), you may face the late enrollment penalty. It is permanent and continues for as long as you have Part B coverage.

Exceptions to the Part B Penalty

While most individuals are subject to the Medicare Part B penalty if they delay enrollment without creditable coverage, there are a few exceptions to be aware of:

1. Employer Coverage: If you have employer-provided health insurance and plan to continue working beyond the age of 65, you may be eligible for a Special Enrollment Period (SEP) that allows you to enroll in Part B without facing a penalty once you retire and lose your employer coverage.

2. Medicaid and Medicare Savings Programs: If you qualify for a Medicare Savings Program, your state pays your Part B premium, and the Part B late enrollment penalty does not apply while you’re enrolled. (The separate Extra Help program eliminates the Part D late enrollment penalty.)

3. Veterans’ Benefits and TRICARE: Be careful here. VA health coverage does not count as creditable coverage for Part B, and losing it does not trigger a Special Enrollment Period, so veterans who delay Part B based on VA coverage alone can still face the penalty. TRICARE rules vary by program, and TRICARE For Life requires you to enroll in Part B. Check with the VA or TRICARE before deciding to delay.

The Importance of Timely Enrollment

Considering the potential penalties and increased healthcare costs associated with delaying Medicare Part B, it is crucial to evaluate your individual situation. While there may be valid reasons to delay enrollment, such as maintaining employer coverage, it’s essential to plan and ensure you enroll in Part B promptly when your circumstances change.

If you are approaching the age of 65 and planning to work beyond that age, take the following steps:

• Review Your Employer Coverage: Understand the details of your employer-provided health insurance plan and how it coordinates with Medicare. This will help you determine if you need to enroll in Medicare Part B immediately or if you can delay without facing a penalty.

• Consider the Special Enrollment Period (SEP): If you plan to delay Medicare Part B enrollment due to active employment, you may qualify for a Special Enrollment Period once you retire. This allows you to enroll in Part B without penalty. Check with your employer’s benefits department or consult a Medicare professional to determine your eligibility for this SEP.

• Evaluate Your Health Needs: Assess your current health status and medical needs. If you have pre-existing conditions or anticipate the need for extensive medical care, enrolling in Medicare Part B promptly may provide comprehensive coverage and peace of mind.

• Plan for the Future: While delaying Medicare Part B enrollment may have short-term benefits, consider your long-term plans. Evaluate the potential costs and penalties you may face in the future. It’s essential to balance immediate financial considerations with the need for comprehensive healthcare coverage as you age.

• Seek Professional Advice: Schedule a consultation with SmartConnect. Their licensed agents can help you understand the implications of delaying enrollment and guide you toward the best decision for your circumstances.

What are the advantages to signing up for Medicare during the Initial Enrollment Period?

By signing up for Medicare during your Initial Enrollment Period (IEP), you’ll get a variety of benefits. You’ll be able to transition smoothly to Medicare from your previous health insurance, and you won’t have to worry about any lapse in your routine health care appointments or daily prescriptions. Plus, you’ll never have to worry about late enrollment penalties or proving your creditable coverage.

You also open up your coverage options beyond your basic health care plan. You can purchase auxiliary coverage that is specifically designed to work with Medicare, like Medicare Supplement Insurance. Joining a Medigap plan during your initial enrollment window guarantees coverage without any health checks and gets you the lowest possible rate for that plan.

Five common Medicare enrollment mistakes and how to avoid them

Medicare enrollment can feel like navigating a maze. With its different parts, enrollment periods, and plan types, it’s easy to feel overwhelmed. Unfortunately, making a mistake during enrollment can lead to unexpected costs, coverage gaps, or limitations on seeing your preferred doctors. By understanding a few common pitfalls, you can approach Medicare enrollment with confidence.

Mistake #1: Assuming Medicare is free

While you likely paid Medicare taxes throughout your working life, and some parts might not have a monthly premium, healthcare is not free.

• The Reality: Even with premium-free Part A, Part B (medical insurance) has a standard monthly premium (and potentially higher costs based on income). Both Original Medicare (Parts A & B) involve deductibles and coinsurance (typically 20% for Part B services after the deductible). Medicare Advantage (Part C) plans, even those with a $0 premium, have out-of-pocket costs like copayments and deductibles for services. Prescription Drug Plans (Part D) also have premiums and cost-sharing.

• How to Avoid It: Budget for healthcare costs beyond just premiums. When comparing plans (Original Medicare + Supplement vs. Medicare Advantage), carefully review the Summary of Benefits and Evidence of Coverage documents to understand deductibles, copays, coinsurance, and the plan’s maximum out-of-pocket limit. In addition, if you see advertisements referring to no-cost or $0 plans, please be hesitant; these should just be referring to $0 premiums, and that type of language is not compliant with current marketing regulations.

Mistake #2: Missing enrollment deadlines (and paying penalties)

Timing is crucial with Medicare. Missing your specific enrollment window without having other qualifying coverage can lead to lifelong penalties.

• The Reality: Your main enrollment window is your Initial Enrollment Period (IEP), a 7-month period starting 3 months before your 65th birthday month, including your birthday month, and ending 3 months after. If you miss your IEP and don’t qualify for a Special Enrollment Period (SEP) (e.g., losing employer coverage), you might have to wait for the General Enrollment Period (GEP) (January 1 through March 31), and your coverage won’t start until the first of the month after you sign up. Worse, you could face the permanent late enrollment penalties described above, added to your Part B and Part D premiums every month for as long as you have the coverage.

• How to Avoid It: Know your Initial Enrollment Period dates! If you plan to keep working past 65 with employer coverage, understand the rules around Special Enrollment Periods to enroll later without penalty. Mark deadlines on your calendar.

Mistake #3: Not checking provider networks for Medicare Advantage

Having insurance doesn’t guarantee your preferred doctor or hospital will accept it, especially with certain types of Medicare plans.

• The Reality: Original Medicare allows you to see virtually any doctor or hospital in the U.S. that accepts Medicare patients. However, Medicare Advantage (Part C) plans usually have specific networks (like HMOs or PPOs). Seeing providers outside the network can result in significantly higher costs or no coverage at all (except in emergencies).

• How to Avoid It: If considering a Medicare Advantage plan, always check the plan’s provider directory before enrolling. Confirm your essential doctors, specialists, and preferred hospitals are in-network. Don’t just assume. Verify!

Mistake #4: Thinking you don’t need Medicare if you’re still working

If you’re working past 65 and have health insurance through your employer (or a spouse’s employer), you might think you can simply ignore Medicare. This isn’t always the best or correct approach.

• The Reality: Depending on the size of the employer, you might still need to enroll in Part A (it’s often premium-free). You might be able to delay Part B without penalty if the employer coverage is considered “creditable.” However, you should still compare the costs and benefits of your employer plan versus enrolling in Medicare (perhaps Parts A and B, or an Advantage plan). Sometimes Medicare can be primary or secondary insurance, or even a more affordable option.

• How to Avoid It: Don’t assume. Talk to your employer’s benefits administrator to understand how your insurance works with Medicare. Compare the premiums, deductibles, coverage details, and drug costs of your employer plan versus your Medicare options. Determine if your employer coverage is creditable for delaying Part B.

Mistake #5: Not understanding Original Medicare vs. Medicare Advantage

These are two fundamentally different ways to get your Medicare benefits, each with its own structure, costs, and rules. Choosing one without understanding the other can lead to dissatisfaction.

• The Reality:

  • Original Medicare: Run by the federal government (Parts A & B). Offers broad access to providers nationwide. Often paired with a separate Part D drug plan and potentially a Medigap (Medicare Supplement) policy to help cover cost-sharing.

  • Medicare Advantage (Part C): Plans offered by private insurance companies approved by Medicare. Must cover everything Original Medicare does. Often bundles Parts A, B, and D. May include extra benefits (dental, vision). Usually requires using a network of providers. Costs structured differently (e.g., copays).

• How to Avoid It: Assess your healthcare needs, budget, prescription drug usage, and travel habits. Do you prioritize provider choice (Original Medicare) or potentially lower premiums and extra benefits with network limitations (Medicare Advantage)? Research both options thoroughly. Remember that Medicare Advantage replaces Original Medicare; if you stay with Original Medicare, a Medigap plan supplements Original Medicare.

Choose wisely, enroll confidently

Medicare doesn’t have to be a source of stress. Understand the potential penalties, evaluate your health needs, and know your deadlines. By being aware of these common mistakes, from understanding costs and minding deadlines to checking networks, comparing options even while employed, and knowing the core differences between Original Medicare and Medicare Advantage, you can make informed choices.

Take your time, and do your research. Making the right Medicare decisions upfront can positively impact your health and financial well-being for years to come. Learn more in our Guide to Medicare Enrollment Periods.

Where can I get help with understanding my Medicare options?

Navigating Medicare enrollment and understanding the penalties can be complex. It’s highly recommended to seek guidance from a qualified insurance agent or a certified Medicare counselor who can provide personalized advice based on your specific situation. Benepicks partners with SmartConnect, whose licensed insurance agents specialize in Medicare comparison shopping and can help you find the most appropriate plan for your needs, at no cost. Through a simple, no-obligation consultation, they can evaluate your coverage options and your eligibility for Special Enrollment Periods. Contact support@benepicks.com for more help.

This article is for educational purposes only and is not tax, legal, or insurance advice. Benepicks is not connected with or endorsed by the U.S. government or the federal Medicare program.