You can change Medicare Supplement plans during specific windows each year, and some life changes let you switch outside those windows

Medicare Supplement plans (also called Medigap) are not locked in for life. You have may provide windows to switch every year, and certain events — like turning 65, moving to a new state, or losing other coverage — open additional windows where insurers cannot deny you or charge more based on your health. The catch is that timing matters. Miss your window and you may face medical underwriting, which means the insurer can refuse you or price you higher based on pre-existing conditions.

The rules are set by federal law, but the exact dates and what counts as a may have access to event can vary by state and by your personal situation. This guide walks you through when you can switch, what paperwork you need, and what happens if you miss a important date.

Key Takeaways

  • You can switch Medicare Supplement plans during your open enrollment period (October 15 to December 7 each year) without the insurer asking about your health.
  • If you turn 65 and enroll in Medicare Part B for the first time, you have a six-month window to buy any Medigap plan at the lowest price, regardless of health history.
  • Moving to a new state, losing employer coverage, or having your current plan leave the market are may have access to life events that may open a special enrollment window outside the annual period.
  • If you switch outside a may provide window, the insurance company can review your health and may deny coverage or charge higher premiums.
  • You must contact the new insurance company directly to switch; Medicare does not process Medigap changes.

The Annual Open Enrollment Period: October 15 to December 7

Every year, all Medicare beneficiaries get a may provide window to switch Medigap plans. This period runs from October 15 to December 7. During these dates, any insurance company selling Medigap in your state must accept your request to switch, and they cannot charge you more or deny you based on your health history or claims.

This is the safest time to switch. You can move from one plan to another, or even from one insurance company to a different one, with no medical questions asked. The new coverage typically starts on January 1 of the following year, though some insurers may offer earlier start dates if you enroll early in the window.

You do not need to wait until October to start researching. Many people compare plans and rates in September so they are ready to contact insurers on October 15. Plans and premiums change year to year, so even if you are happy with your current plan, it is worth checking whether a different plan or company offers better value.

The Initial Enrollment Period: Six Months After You Turn 65

If you are new to Medicare, you have a six-month open enrollment period that starts the month you turn 65 and enroll in Medicare Part B. During this window, you can buy any Medigap plan sold in your state at the lowest available price. Insurance companies cannot refuse you or charge more based on any health condition you have, no matter how serious.

This window is one of the most valuable protections in Medicare law. If you have diabetes, heart disease, or any other condition, you still pay the same premium as a healthy person during this period. Once the six months end, that protection goes away — if you try to switch plans after this window closes, the insurer can underwrite your health and may deny you or charge significantly more.

The exact dates depend on when you turn 65. If you turn 65 in March and enroll in Part B that month, your six-month window runs from March through August. If you delay enrolling in Part B, your window starts when you actually enroll, not when you turn 65. This is why timing your Part B enrollment matters if you do not have other health coverage.

may have access to Life Events That Open Special Windows

Outside the annual enrollment period and your initial six-month window, you can switch Medigap plans if you experience certain life changes. These are called may have access to events, and they give you a limited window — usually 30 to 60 days, depending on your state — to switch without medical underwriting.

Common may have access to events include:

  • Moving to a new state or a new area where your current plan is no longer available
  • Your current Medigap plan being discontinued or withdrawn from the market
  • Losing employer-sponsored retiree health coverage
  • Losing coverage under a spouse's employer plan due to divorce or death
  • Turning 65 and losing Veterans Affairs (VA) coverage or Tricare (military family coverage)
  • Losing coverage under a state pharmaceutical information program

If any of these happen to you, contact your state's insurance commissioner's office or your State Health Insurance information Program (SHIP) to confirm you have a may have access to event and to learn your state's specific important date. Do not assume — the rules vary by state, and missing the window can cost you.

What Happens If You Miss Your Window

If you try to switch Medigap plans outside a may provide enrollment period and without a may have access to event, the insurance company can perform medical underwriting. This means they review your health history, current medications, and past claims. They can then refuse to sell you the plan, or they can sell it to you at a higher premium than they charge healthier applicants.

Some states have rules that limit how much more an insurer can charge based on health (called rating restrictions), but these vary widely. In some states, an insurer can charge you 50% more than the standard rate. In others, the limits are different. A few states have stricter protections, but most do not.

This is why staying within a may provide window matters. If you know you want to switch, mark October 15 on your calendar. If a may have access to event happens, act quickly and document it — keep letters from your employer, your insurance company, or your state program that explain why your coverage ended.

How to Switch Plans: Steps and Timing

To switch Medigap plans, you contact the new insurance company directly — not Medicare. You can find Medigap insurers in your state through Medicare.gov's plan finder tool, or by calling 1-800-MEDICARE. Have your current Medicare card and your Social Security number ready when you call.

When you contact the new insurer, tell them you want to enroll in a specific Medigap plan (for example, Plan G or Plan N). They will ask whether you are switching during a may provide enrollment period or because of a may have access to event. If you are, tell them the date and the reason. If you are not, they will ask health questions.

Once you enroll, the new insurer will send you a confirmation letter with your effective date and your first premium amount. Your old Medigap plan does not automatically cancel — you should contact your current insurer and ask them to terminate your coverage on the date your new plan starts. This prevents you from paying premiums to both plans.

The entire process usually takes one to two weeks from enrollment to receiving your new card and confirmation. Plan ahead if you want your new coverage to start on a specific date, especially if you are switching during the annual enrollment period when many people are making changes.

State Variations and Where to Get Help

Medicare Supplement rules are federal, but states can add their own protections and set their own important date for may have access to events. For example, some states give you 60 days to switch after a may have access to event; others give 30 days. Some states allow switching if your premium increases above a certain threshold; others do not.

Your State Health Insurance information Program (SHIP) is a free resource that knows your state's specific rules. You can find your state's SHIP by calling 1-800-MEDICARE or visiting the Eldercare Locator at 1-800-677-1116. SHIP counselors can tell you whether a particular event qualifies you for a special enrollment window in your state and what important date you are working with.

If you are considering a switch, SHIP can also help you compare plans and understand the differences between them. They do not sell insurance and have no financial stake in which plan you choose, so their information is independent.

Frequently Asked Questions

Can I switch Medigap plans in the middle of the year if my premium goes up?

Not unless your state has a specific rule allowing it or your situation qualifies as a life event. Most states do not allow switching just because of a rate increase. Your best opportunity is the annual October 15 to December 7 window. Some states do allow a switch if your premium increases by more than a certain percentage, so check with your state's insurance commissioner or SHIP.

What if my Medigap plan is discontinued?

If your insurance company stops selling your plan, they must notify you in advance and give you options — usually the chance to switch to another plan from the same company without medical underwriting. If you want to switch to a different company's plan, you typically have 30 to 60 days from when your plan ends. Contact your current insurer for the exact important date.

Do I have to switch plans when I turn 65?

No. You can keep the same plan for as long as it is available and you want it. But if you do not have Medigap when you turn 65 and enroll in Part B, your six-month open enrollment window is your best chance to get coverage without medical underwriting. After that window closes, switching becomes harder and more expensive.

Can I switch from one Medigap plan to another with the same insurance company?

Yes, and you can do this during the annual enrollment period without medical underwriting. Some states also allow you to switch plans with the same company outside the enrollment period, but the rules vary. Contact your current insurer to ask whether they allow mid-year switches between their own plans.

What if I am denied coverage when I try to switch outside a may provide window?

You can appeal the denial to your state's insurance commissioner. You can also contact SHIP or your state's long-term care ombudsman for help filing a complaint. Keep all letters from the insurance company that explain why they denied you, as these are important for an appeal.