Medicare Enrollment Rights 2027: Dates, Rules and Protections

Key Medicare Enrollment Periods for 2027

Medicare enrollment periods are designated windows set by CMS during which beneficiaries can join, switch, or drop Medicare health and drug plans. Knowing the Medicare enrollment periods 2027 is the first step toward avoiding a coverage gap or missing a window that only comes around once a year.

AEP is still the main time to join or change Medicare coverage. If you miss it and don't have a qualifying Special Enrollment Period (SEP), you'll typically have to wait until the following fall to make a change. For a rundown of the most common missteps beneficiaries make during this window, see our guide on AEP mistakes to avoid before you finalize a decision.

Understanding Your Medicare Plan Choice Rights

As the official United States government Medicare handbook notes, every person with Medicare has rights and protections guaranteed by CMS. These include the right to be treated with courtesy, dignity, and respect, and the right to have personal and health information kept private.

One of the biggest Medicare plan choice rights is guaranteed-issue rights. Sometimes referred to as Medigap protections, these rights allow you to buy a Medicare Supplement (Medigap) policy without medical underwriting. Insurance companies cannot deny you coverage, charge you more, or impose waiting periods for pre-existing conditions when these rights apply.

These Medigap guaranteed-issue rights enable you to enroll outside of your initial Medigap Open Enrollment Period. You may qualify for a guaranteed-issue window if:

• You're enrolled in a Medicare Advantage plan that terminates, stops serving your area, or violates its contract with CMS.
• You move out of the service area of your current plan.
• You're in your first year in a Medicare Advantage plan (Trial Right #1).
• You were previously in a Medicare Supplement plan and want to re-enroll in that same plan (Trial Right #2).
• Your employer or union group health coverage ends.
• Your state of residence has a Birthday Rule that qualifies you annually.

The Centers for Medicare & Medicaid Services (CMS) mandates that Medicare Advantage and Part D plans provide crucial documents in multiple languages and accessible formats to ensure equitable access for beneficiaries with limited English proficiency (LEP) and disabilities. Plans must translate required materials into any non-English language spoken by at least five percent of the population in their service area, and beneficiaries are entitled to receive information in accessible formats such as braille, large print, and audio files (MP3/DVD) or digital formats compatible with screen readers.

Special Enrollment Periods (and When They Apply)

A Special Enrollment Period is a designated window outside standard enrollment periods that allows eligible Medicare beneficiaries to join, switch, or drop plans due to qualifying life events. There are no new SEPs for 2027.

Common Medicare SEP triggers include:

• Plan discontinuation or exit from your service area
• A change in your Medicaid or Extra Help (Low-Income Subsidy) status
• Automatic Part D enrollment scenarios tied to Extra Help eligibility
• The Five-Star SEP, which lets you join a five-star Medicare Advantage or Part D plan once during the December 8 to November 30 window
• Moving out of your plan's service area
• Loss of employer or union coverage

Outside the initial, annual, and special enrollment periods, Medicare enrollment options are limited. That makes acting quickly on a qualifying life event Medicare essential to avoiding a coverage gap.

Medicare Advantage Trial Rights Explained

In Trial Right #1, if you join a Medicare Advantage plan for the first time, you have 12 months to disenroll and return to Original Medicare with guaranteed-issue rights to purchase any Medigap plan sold in your state. During the Medicare Advantage OEP, you can also switch from Medicare Advantage back to Original Medicare (plus a standalone Part D plan).

In trial Right #2, if you dropped a Medicare Supplement plan to try Medicare Advantage for the first time, you can return to that same Medigap plan. Or, if it's no longer available, you can select a standardized plan with equal or lesser benefits within 12 months without medical underwriting.

If you need Medigap coverage after leaving Medicare Advantage outside of these trial rights, medical underwriting may be required in some cases, which makes it essential for you to understand Medicare Advantage trial rights before you switch. For more on moving from Medicare Advantage back to Medigap coverage, see our guide on switching from Medicare Advantage to Medigap.

How Plan Terminations and Moves Affect Your Enrollment Options

When a Medicare Advantage or Part D plan is discontinued, affected enrollees typically receive advance notice and may qualify for guaranteed-issue rights to enroll in Medigap if they return to Original Medicare. It’s important to read that notice the day it arrives or soon thereafter.

Plan terminations generally fall into one of three scenarios:

• The plan stops operating entirely.
• The plan withdraws from your county or service area.
• The plan violates its contract with CMS.

Moving creates a different SEP. If you move out of the area your plan serves, you generally have a window of at least two months to enroll in a new Medicare Advantage plan in your new area or switch to Original Medicare with a Medigap policy.

Once you have Parts A and B, you can join Medicare Advantage wherever a plan serves your new address. If your plan is being terminated:

1. Read your termination notice as soon as it arrives.
2. Identify your Special Enrollment Period window.
3. Compare the plans available in your area.
4. Enroll in a new plan, or exercise your guaranteed-issue Medigap rights.
5. Confirm your enrollment before the deadline.

State-Specific Enrollment Protections

The Medigap Birthday Rule is a state-level protection that offers Medicare beneficiaries a guaranteed-issue window, typically 30 to 63 days around their birthday, to switch to a new Medicare Supplement plan of equal or lesser benefit without medical underwriting. As of 2026, sixteen states have active Medigap Birthday Rules. New Mexico is scheduled to join the ranks in 2027. Other states that recently adopted the Birthday Rule include Indiana, Delaware, West Virginia, and Virginia.

Always verify your own state Medicare Supplement protections before assuming a switch is available where you live. The Birthday Rule affects Medicare enrollees financially because premiums for the same Medigap plan letter can vary significantly between insurers. However, the annual window lets you shop for a lower rate without answering any health questions.

For a deeper look at how the Birthday Rule works state by state, including guidance built for both consumers and the agents who serve them, see our full Birthday Rule guide for insurance agents.

Importance of Reviewing Your Annual Notice of Change

The Annual Notice of Change (ANOC) is a document your Medicare Advantage or Part D plan sends each September detailing changes to premiums, copays, drug formularies, and provider networks that will take effect the following January 1. ANOC letters are distributed in September and explain premium, copay, and drug coverage changes. ANOC letters also cover whether your doctors and hospitals remain in network.

When your ANOC document arrives, check for:

• Premium changes
• Copay and coinsurance adjustments
• Formulary additions or removals affecting your current drugs
• Network changes affecting your doctors and hospitals
• New prior authorization rules
• Plan discontinuation notices

Because widespread plan exits are expected heading into 2027, a careful ANOC review is one of the most important things you can do to ensure you’re enrolled in the proper Medicare plan. If you miss AEP while your plan still exists, you may be automatically re-enrolled. Nevertheless, that doesn't mean your coverage terms have not changed.

Practical Steps to Protect Your Medicare Coverage in 2027

With all these rights, windows, and rules in mind, follow this checklist each year to make sure nothing slips through the cracks.

1. Read your ANOC immediately when it arrives in September, noting any discontinuation, formulary change, or network shift.
2. Identify your enrollment window (i.e., AEP, MA OEP, or SEP).
3. Compare plans thoroughly using Medicare Plan Finder and plan materials, reviewing premiums, networks, formularies, and prior-authorization rules.
4. Check for guaranteed-issue rights tied to plan termination, a move, trial rights, employer coverage loss, or your state's Birthday Rule.
5. Independently verify provider directories by cross-checking with your doctors' offices directly. Known Plan Finder accuracy issues prompted the new temporary SEP for 2027.
6. Enroll before your deadline; AEP coverage starts January 1, and Medicare Advantage OEP changes take effect the first of the month after enrollment.
7. Confirm your enrollment is processed correctly by contacting your new plan or calling 1-800-MEDICARE.

If you switch to Original Medicare, remember that you might need a separate Part D drug plan and may want to add Medigap coverage. For help comparing Medigap options against your specific needs, see our guide on matching Medicare Supplement plans to client profiles.

Resources for Medicare Enrollment Decisions

We understand that the Medicare enrollment process can seem confusing. These resources can answer specific questions, confirm your eligibility, or connect you with someone who knows your options inside and out.

• AAMSI | MedicareSupp.org: a free portal for comparing Medicare prescription drug plans and connecting directly with licensed local agents who can review your specific situation
• 1-800-MEDICARE (1-800-633-4227): available 24/7 for enrollment questions, SEP eligibility checks, and plan comparisons
• State Health Insurance Assistance Program (SHIP): free, unbiased counseling from trained volunteers in every state
• Medicare.gov and Medicare Plan Finder: official comparison tools, though cross-checking directories directly with providers is recommended
• Medicare & You Handbook: CMS's annual guide to rights, enrollment mechanics, and Extra Help

Remember, you can request Medicare information in a language you understand and in accessible formats. If you receive Supplemental Security Income (SSI), Medicare automatically mails a purple letter about Extra Help without a separate application required. If Medicare enrolls you in a drug plan on your behalf, you'll receive a yellow or green letter.

For quick answers to more Medicare Supplement questions, visit our FAQ page. Or, start at MedicareSupp.org to connect with a licensed agent for personalized guidance.

Frequently Asked Questions

When is Medicare open enrollment for 2027?

The Medicare Annual Enrollment Period for 2027 plans runs from October 15 to December 7, 2026. Any changes you make during this window take effect on January 1, 2027.

What changes can I make during Medicare open enrollment?

During the Annual Enrollment Period, you can switch Medicare Advantage plans, change your Part D prescription drug plan, move from Medicare Advantage to Original Medicare, or enroll in a Medicare Advantage plan from Original Medicare.

What are Medicare guaranteed-issue rights for Medigap?

Guaranteed-issue rights allow you to buy a Medicare Supplement plan without medical underwriting. You qualify when specific events occur, such as your Medicare Advantage plan terminating, moving out of your plan's service area, or exercising a trial right after trying Medicare Advantage.

What are Medicare Advantage trial rights?

Trial Right #1 gives you 12 months to leave a Medicare Advantage plan and return to Original Medicare with guaranteed-issue Medigap enrollment if it's your first time in Medicare Advantage. Trial Right #2 allows you to return to your previous Medigap plan if you dropped it to try Medicare Advantage for the first time.

What is the Medigap Birthday Rule?

The Medigap Birthday Rule is a state-level protection in certain states that gives you a guaranteed-issue window around your birthday each year to switch Medicare Supplement plans without medical underwriting, typically to find a lower premium.

Can I change my Medicare plan after December 7?

In some cases, yes. If you have Medicare Advantage, you can use the Medicare Advantage Open Enrollment Period from January 1 through March 31 to make one plan change. You may also qualify for a Special Enrollment Period based on a qualifying life event.

What should I do if my Medicare plan is being discontinued?

Review your plan's termination notice immediately, identify your SEP window, compare available plans in your area, and consider whether Original Medicare with a Medigap policy is the right fit. You may have guaranteed-issue rights to enroll in Medigap without medical underwriting.

Where can I get free help with Medicare enrollment?

You can visit MedicareSupp.org to compare plans and connect with a licensed local agent, call 1-800-MEDICARE, or contact your State Health Insurance Assistance Program for free and unbiased counseling.

What is an Annual Notice of Change, and why does it matter?

The Annual Notice of Change is a document sent by your Medicare Advantage or Part D plan each September that details upcoming changes to premiums, copays, drug coverage, and provider networks. Reviewing it helps you avoid unexpected costs or coverage gaps.