Key Takeaways

• You can delay Medicare Part B without penalty if you have creditable coverage from a current employer, but the timing of enrollment is critical.

• Missing the correct window to enroll after your coverage ends may result in lifelong penalties and late enrollment gaps.

Understanding When It Makes Sense to Delay Medicare Part B

Enrolling in Medicare Part B is a major decision that affects both your finances and healthcare access. While many people sign up at age 65, that isn’t always the best option. Depending on your work status, other insurance, and financial goals, delaying Medicare Part B could be wise—or costly.

To avoid penalties, you need to understand exactly when you can delay, how long you can postpone, and what steps to take once you need coverage. This article walks you through the timing, rules, and special enrollment periods that determine whether delaying Medicare Part B makes sense for you.

What Does Medicare Part B Cover?

Before considering any delay, it’s important to know what you’re deferring. Medicare Part B covers outpatient medical services, such as:

• Doctor visits

• Preventive services

• Lab tests and imaging

• Durable medical equipment

• Outpatient surgeries

• Mental health care

In 2025, the standard monthly premium for Medicare Part B is $185, and the annual deductible is $257. Once that deductible is met, Medicare typically pays 80% of the approved amount for covered services.

When You’re Automatically Enrolled vs. When You Must Take Action

If you’re already receiving Social Security or Railroad Retirement Board benefits at least four months before you turn 65, you’ll be automatically enrolled in Parts A and B.

If you are not yet receiving Social Security benefits, you must sign up manually during your Initial Enrollment Period (IEP), which begins three months before the month you turn 65, includes your birthday month, and ends three months after. This seven-month window is critical.

If you plan to delay Part B, you must actively decline it when you become eligible. Otherwise, you may be enrolled and charged premiums regardless of whether you need the coverage.

Situations Where Delaying Part B Might Be the Right Move

Delaying Medicare Part B is generally safe if you meet specific conditions. Most commonly, these involve having coverage through an employer.

1. You or Your Spouse Is Still Working

If you or your spouse is actively employed and you are covered under a group health plan provided by that employer, you can delay Part B without penalty. This exception applies only if the employer has 20 or more employees.

In this case, Medicare considers the employer plan to be primary insurance, and you can defer Part B until you (or your spouse) stop working or lose that coverage. Once that happens, you get an eight-month Special Enrollment Period to sign up for Part B.

2. You Have Coverage Through a Union Plan

Some union health plans may offer coverage that counts as creditable. You need written confirmation from the plan to verify that the coverage meets Medicare’s standards. If the coverage is creditable, you can safely delay enrolling in Part B.

3. You Have TRICARE, CHAMPVA, or VA Benefits

These government-sponsored plans often intersect with Medicare in complex ways. Generally, you must enroll in Part B to maintain these benefits once you’re eligible for Medicare. However, if you’re actively serving in the military, you can delay Part B without penalty until you retire.

When You Should NOT Delay Part B

Even if you have some form of insurance, it may not be enough to delay Medicare Part B. Delaying in these situations could result in serious penalties.

1. Retiree Health Insurance

Coverage from a former employer (retiree benefits) is not considered creditable for delaying Part B. Medicare will be your primary coverage once you turn 65. You should enroll during your Initial Enrollment Period to avoid gaps and penalties.

2. COBRA Coverage

COBRA is a temporary extension of your employer coverage, not active employer coverage. It does not qualify as creditable for delaying Part B. If you wait until COBRA ends to enroll in Part B, you could face a late enrollment penalty and may have to wait until the next General Enrollment Period.

3. Marketplace or Individual Health Insurance

Health plans bought through the Health Insurance Marketplace (or directly from a private insurer) do not count as creditable coverage for Medicare. You must enroll in Part B when first eligible, or you risk late penalties and potential loss of access to subsidized coverage.

Understanding the Late Enrollment Penalty

If you delay Medicare Part B and don’t have creditable coverage, you will pay a penalty that lasts for life. The penalty is 10% of the standard Part B premium for each 12-month period you went without coverage.

For example, if you delay enrollment by two full years, you would pay 20% more on your monthly Part B premium every year going forward. In 2025, that would increase your monthly cost from $185 to $222.

How the Special Enrollment Period Works

If you delay Medicare Part B because you have creditable employer coverage, you will qualify for a Special Enrollment Period (SEP) when that coverage ends.

• The SEP lasts for eight months from the date your employment or employer coverage ends, whichever comes first.

• You can enroll in Medicare Part B at any point during this eight-month window without penalty.

• Your coverage will begin the month after you enroll, or you can choose a later start date within that SEP.

Acting within the SEP is crucial. If you miss it, you must wait for the General Enrollment Period (January 1 to March 31), and your coverage will not begin until July 1 of that year. You will also incur a late enrollment penalty.

How to Prove You Had Creditable Coverage

To qualify for a penalty-free Special Enrollment Period, you must provide two forms:

• Form CMS-L564: Request for Employment Information, completed by your (or your spouse’s) employer.

• Form CMS-40B: Application for Enrollment in Medicare Part B.

These forms must be submitted to Social Security during your Special Enrollment Period. Delays in documentation can delay your coverage start date.

Timing Strategies to Avoid Coverage Gaps

Careful timing can help you avoid a lapse in coverage:

• If you know your employer coverage will end on June 30, submit your Medicare Part B enrollment in early June so coverage begins July 1.

• If you wait until July 31 to apply, coverage will not start until August 1, leaving you exposed for a month.

If your goal is seamless coverage, plan enrollment one month before employer coverage ends.

What If You’re Approaching Retirement but Not Yet 65?

If you plan to retire after 65 and currently have employer coverage, you can delay Part B until you stop working. Once you retire, the eight-month Special Enrollment Period begins. But if you retire before turning 65, you will need to enroll in Medicare when you reach your Initial Enrollment Period, even if COBRA is available.

Should You Delay If You’re on a Health Savings Account (HSA)?

Medicare enrollment disqualifies you from making contributions to a Health Savings Account. If you wish to continue contributing to your HSA, you may want to delay Part B. However, once you stop contributing or retire, you should enroll promptly to avoid penalties.

In most cases, you should stop HSA contributions six months before enrolling in Medicare, as Medicare coverage can be retroactive for up to six months.

Coordinating Part B with Other Medicare Parts

Delaying Part B also affects your ability to enroll in other parts of Medicare, such as:

• Part C (Medicare Advantage): You must have both Parts A and B to join.

• Part D (Prescription Drug Coverage): Delaying Part B may not directly impact Part D eligibility, but timing matters if you want to avoid the Part D late enrollment penalty.

Making an Informed Decision About Timing

Delaying Medicare Part B can save you money if you’re still working and covered by a qualified group plan. But it can cost you significantly if you delay without proper coverage.

The decision comes down to three factors:

• Are you (or your spouse) still working and covered under an employer plan?

• Does that employer have at least 20 employees?

• Are you ready to track and act within the enrollment periods?

If the answer to any of these is no, then delaying Medicare Part B might not be safe.

Don’t Let Timing Mistakes Lead to Penalties

Your Medicare choices affect your access to care and your wallet for the rest of your life. If you’re unsure about when or whether to delay Medicare Part B, speak with someone who understands the rules inside and out. A licensed agent listed on this website can walk you through your specific situation and help you avoid penalties.