Medicare guidance

Medicare Enrollment Periods: When to Sign Up or Change Coverage

Choose the path that matches the coverage you need to start or change. Parts A and B, Medicare Advantage, Part D and Medigap do not share one universal enrollment window.

Medicare Enrollment Guides: a roadmap leading from a calendar and retirement folder to Medicare coverage choices.
First identify the coverage—then the enrollment period.

Use the first-time guides for Medicare Parts A and B. Use the working and retirement guides when employer coverage changes that timeline. If you already have Medicare, use the annual, Medicare Advantage Open Enrollment or Special Enrollment Period guides for the specific plan change you are considering.

VA health care, TRICARE For Life and CHAMPVA have distinct Part B and coordination rules. Use the Veterans and Medicare hub before treating military or veterans coverage like an employer plan.

Enrollment Path

Start Here

Enrollment Path

First-Time Parts A and B Enrollment

Enrollment Path

Working, Retiring and Other Coverage

Enrollment Path

Annual Medicare Advantage and Part D Changes

Enrollment Path

Special Enrollment Periods and Coverage Events

Related Timing

Medigap Enrollment Is Different

Enrollment Path

Special and Local Situations

Before Making a Change

Information to Gather

  • Your expected retirement and coverage-end dates.
  • Whether coverage is based on current employment.
  • The employer’s official Medicare coordination size.
  • Your Social Security or Railroad Retirement status.
  • Any HSA contributions by you or the employer.
  • Doctors, facilities, prescriptions and pharmacies.
  • The spouse or dependents who need replacement coverage.
Common Questions

Frequently Asked Questions

When should I begin preparing for Medicare?

Begin at least three months before the desired start date. Six months gives more time when employer coverage, an HSA, retirement or a spouse’s coverage is involved.

Does everyone automatically receive Medicare at 65?

No. Automatic enrollment generally depends on receiving qualifying Social Security or Railroad Retirement benefits before age 65.

Can I delay Medicare because I am still working?

Possibly, when you have qualifying group coverage based on current employment. Employer size and payer order must also be confirmed.

Does COBRA extend my Part B enrollment period?

No. COBRA does not extend the working-aged Part B Special Enrollment Period.

Can Marketplace coverage replace Medicare at 65?

Most people eligible for premium-free Part A should enroll in Medicare and generally lose eligibility for Marketplace financial assistance for their own coverage.

Do I need to stop HSA contributions?

Yes, for Medicare-covered months. Retroactive premium-free Part A can require contributions to stop months before an application.

Can Thompson Medicare Brokerage enroll me in Parts A and B?

No. Social Security or the Railroad Retirement Board handles Parts A and B. We help compare the private Medicare coverage choices that follow.

Independent Medicare guidance

Build the Enrollment Path Around Your Actual Coverage

Benjamin Thompson can help people in Missouri and Illinois compare the private Medicare options represented by Thompson Medicare Brokerage and organize the questions to take to Social Security, employers, the Marketplace or a tax professional.