How to Switch Medicare Plans: Step-by-Step Guide

Why People Switch Medicare Plans

Your Medicare plan is not a life sentence. Every year, insurers change their premiums, formularies, provider networks, and benefits. A plan that worked perfectly for you this year might raise your copays, drop your pharmacy, or remove a medication from its formulary next year. When that happens, you have the right to switch — but only during specific enrollment windows and only if you follow the correct process.

Maybe you moved to a new state and your Medicare Advantage plan does not cover providers in your area. Maybe your doctor left your plan's network. Maybe you are paying too much for prescriptions and want a Part D plan with a better formulary. Or maybe you enrolled in Medicare Advantage and realized you would prefer the flexibility of Original Medicare with a Medigap supplement.

Whatever the reason, switching Medicare plans is not difficult once you understand the rules. This guide walks you through every type of switch, when you can make each one, and the pitfalls that could leave you with gaps in coverage or higher costs.

When You Can Switch Medicare Plans

You cannot change your Medicare coverage whenever you want. The federal government defines specific enrollment periods during which you are allowed to make changes. Understanding which window applies to your situation is the first step in any plan switch.

Annual Election Period (AEP): October 15 to December 7

The Annual Election Period is the primary window for plan changes. Every Medicare beneficiary can use it, regardless of what type of coverage they have. During the AEP you can switch from one Medicare Advantage plan to another, move from Original Medicare to Medicare Advantage (or back again), join or switch a Part D prescription drug plan, or drop Part D coverage entirely. Any changes you make take effect on January 1 of the following year.

Medicare Advantage Open Enrollment Period (OEP): January 1 to March 31

This window is exclusively for people who are currently enrolled in a Medicare Advantage plan at the start of the year. During the OEP, you can switch to a different Medicare Advantage plan or drop your Advantage plan and return to Original Medicare (and pick up a standalone Part D plan). You can only make one change during this period, and the new coverage typically starts the first of the month after you enroll. People on Original Medicare cannot use the OEP to join an Advantage plan.

Special Enrollment Periods (SEPs)

Special Enrollment Periods open up outside the normal schedule when specific life events occur. You may qualify for an SEP if you move out of your plan's service area, lose employer coverage, qualify for Medicaid or Extra Help, are released from incarceration, or if your plan terminates or receives low quality ratings (below 3 stars). Each SEP has its own timeframe, but most give you about two months from the qualifying event to make a change.

Medigap Open Enrollment Period

Your Medigap Open Enrollment Period is a one-time, 6-month window that begins on the first day of the month you are both 65 or older and enrolled in Medicare Part B. During this window, insurance companies must sell you any Medigap policy they offer at the best available rate, regardless of your health status. They cannot deny you coverage or charge you more because of pre-existing conditions. Once this window closes, switching Medigap plans becomes much harder because insurers can use medical underwriting to deny your application or charge you higher premiums.

How to Switch From One Medicare Advantage Plan to Another

Switching between Medicare Advantage plans is the most common type of Medicare plan change and, fortunately, one of the most straightforward. You can make this switch during either the AEP or the OEP.

Step-by-step process

1. Review your Annual Notice of Change (ANOC). Your current plan must send you this document by September 30 each year. It details every change to your plan's costs, benefits, formulary, and provider network for the coming year. Read it carefully — this is often what triggers people to start shopping.
2. Use the Medicare Plan Finder. Go to medicare.gov/plan-compare and enter your zip code, medications, preferred pharmacies, and doctors. The tool will show you every Advantage plan available in your area along with estimated annual costs.
3. Compare plans on what matters most. Look at the monthly premium, annual deductible, maximum out-of-pocket (MOOP) limit, copays for primary care and specialist visits, drug formulary coverage, and star rating. Make sure your doctors and hospitals are in network.
4. Enroll in the new plan. You can enroll online at the plan's website, call the plan directly, use medicare.gov, call 1-800-MEDICARE, or work with a licensed insurance agent. When you enroll in the new plan, your old plan is automatically canceled — you do not need to call your old plan to disenroll.
5. Confirm your enrollment. You should receive a confirmation letter from the new plan. If you are switching during the AEP, your new coverage starts January 1. If you switch during the OEP, coverage typically starts the first of the month after your enrollment is processed.

There is no coverage gap when switching between Advantage plans. Your old plan remains active until the new plan's effective date, so you are never left without coverage.

How to Switch From Medicare Advantage to Original Medicare

Some people try Medicare Advantage and decide it is not right for them. Maybe the network is too restrictive, prior authorization requirements are getting in the way of care, or they want the freedom to see any doctor who accepts Medicare anywhere in the country. Returning to Original Medicare is absolutely possible, but it requires more planning than switching between Advantage plans.

Step-by-step process

1. Decide on your timing. You can disenroll from Medicare Advantage and return to Original Medicare during the AEP (October 15 to December 7) or the OEP (January 1 to March 31). During the AEP, your Original Medicare coverage starts January 1. During the OEP, it starts the first of the month after you disenroll.
2. Disenroll from your Medicare Advantage plan. You can do this by calling your plan directly, calling 1-800-MEDICARE, or visiting medicare.gov. When you disenroll, you are automatically returned to Original Medicare (Part A and Part B).
3. Enroll in a standalone Part D plan. Most Medicare Advantage plans include prescription drug coverage. When you leave Advantage, that drug coverage goes away. You will need to enroll in a separate Part D plan to maintain prescription drug coverage. Use the Medicare Plan Finder to compare Part D plans in your area.
4. Consider a Medigap (Medicare Supplement) policy. Original Medicare has no out-of-pocket maximum, which means your costs are theoretically unlimited. A Medigap policy fills in the gaps — covering deductibles, coinsurance, and copayments. This is where timing gets critical, and we will explain why in the section on Medigap switching below.
5. Confirm everything is in place. Once your Advantage plan disenrollment is processed, verify with Medicare that you are back on Original Medicare. Confirm your Part D enrollment. If you applied for Medigap, confirm the policy is active before your Advantage plan ends.

Critical warning: If you have been on a Medicare Advantage plan for more than 12 months, you may not have guaranteed-issue rights to buy a Medigap policy. In most states, Medigap insurers can use medical underwriting to deny your application or charge higher premiums based on your health. This is the single biggest consideration when switching from Advantage back to Original Medicare. We cover this in detail in the Medigap section below.

How to Switch From Original Medicare to Medicare Advantage

Moving from Original Medicare to a Medicare Advantage plan is one of the most common switches. Advantage plans often attract people with their $0 premiums, built-in drug coverage, and extra benefits like dental, vision, and hearing that Original Medicare does not cover.

Step-by-step process

1. Make sure you are eligible. To enroll in a Medicare Advantage plan, you must have both Part A and Part B, and you must live in the plan's service area. You also cannot have end-stage renal disease (ESRD) at the time of enrollment, although there are exceptions for certain Special Needs Plans and since 2021 the ESRD restriction has been largely eliminated.
2. Research plans in your area. Use the Medicare Plan Finder at medicare.gov/plan-compare. Enter your zip code, list your doctors, add your prescriptions, and choose your preferred pharmacies. The tool will calculate your estimated total annual cost for each plan.
3. Verify your doctors and hospitals are in network. This is non-negotiable. Unlike Original Medicare, most Advantage plans restrict you to a network of providers. If your primary care doctor or specialists are not in the network, you will pay significantly more to see them — or the plan may not cover them at all (especially with HMOs).
4. Enroll during the AEP. The Annual Election Period (October 15 to December 7) is the standard window for joining an Advantage plan. You can enroll online, by phone, through an agent, or at medicare.gov. Your new Advantage plan starts January 1.
5. Cancel your standalone Part D plan and Medigap policy. When you join a Medicare Advantage plan that includes drug coverage (an MA-PD plan), your standalone Part D plan is automatically terminated. However, you will need to separately cancel your Medigap policy. Keep in mind that once you cancel Medigap, getting it back later may require medical underwriting.

Some states offer a "trial right" for Medigap: if you join a Medicare Advantage plan for the first time and decide within 12 months that you want to go back to Original Medicare, you have a guaranteed right to buy back your Medigap policy (or a comparable one) without underwriting. Check with your State Insurance Department to see if this protection applies in your state.

How to Change Part D Prescription Drug Plans

If you are on Original Medicare with a standalone Part D plan and you want to switch to a different Part D plan, the process is simple. You can only make this change during the Annual Election Period (October 15 to December 7) or during a qualifying Special Enrollment Period.

Step-by-step process

1. List all your current medications. Include the exact drug name, dosage, and quantity. If you use both brand-name and generic medications, note which ones. This list is essential for accurate cost comparisons.
2. Use the Medicare Plan Finder to compare Part D plans. The tool will show you each plan's monthly premium, annual deductible, and your estimated out-of-pocket drug costs based on the specific medications you entered. Pay close attention to which formulary tier your medications fall on — a drug on Tier 2 in one plan might be on Tier 4 in another, which means dramatically different copays.
3. Check pharmacy coverage. Part D plans have preferred pharmacy networks. Using a preferred pharmacy can save you a significant amount on copays. Make sure your regular pharmacy is in the plan's preferred network.
4. Enroll in the new Part D plan. Enroll online at the plan's website, through medicare.gov, by calling 1-800-MEDICARE, or through a licensed agent. When you join a new Part D plan, your old Part D plan is automatically disenrolled — there is nothing additional you need to do.
5. Review your new plan's formulary in January. Once your new plan takes effect January 1, confirm that your medications are still covered at the expected tier and copay. Formularies can occasionally differ from what was projected during enrollment.

Important note about the Inflation Reduction Act: Starting in 2025, Part D out-of-pocket costs are capped at $2,000 per year for all beneficiaries. This cap applies across all Part D plans, but the monthly premiums, deductibles, and formulary coverage still vary widely between plans. The cap does not eliminate the need to comparison-shop.

How to Switch Medigap (Medicare Supplement) Plans

Switching Medigap plans is different from every other type of Medicare plan change. There is no annual enrollment period for Medigap. In most states, you can apply for a new Medigap policy at any time during the year. However, outside of your initial Medigap Open Enrollment Period and a few specific guaranteed-issue situations, insurance companies can use medical underwriting to evaluate your application.

That means if you have developed health conditions since you first enrolled in Medigap, a new insurer can deny your application, exclude coverage for pre-existing conditions, or charge you a much higher premium.

Step-by-step process

1. Compare Medigap rates from multiple insurers. Medigap plans are standardized by letter (Plan A, Plan B, Plan F, Plan G, Plan N, and so on). A Plan G from one company covers the exact same benefits as a Plan G from another company — the only difference is the premium. Get quotes from at least three to five insurers.
2. Check the insurer's pricing method. Medigap insurers use one of three pricing methods: community-rated (everyone pays the same regardless of age), issue-age-rated (your premium is based on your age when you first buy the policy), or attained-age-rated (your premium increases as you get older). Community-rated and issue-age-rated policies tend to be more stable over time.
3. Apply for the new Medigap policy. Submit your application to the new insurer. If medical underwriting is required, you will need to answer health questions and possibly undergo a review of your medical records. The insurer will either approve or deny your application.
4. Do not cancel your old policy until the new one is approved. This is essential. If you cancel your existing Medigap policy before your new application is approved, and the new insurer denies you, you will be left without supplemental coverage and may not be able to get it back. Keep your old policy in force until you have written confirmation that the new policy is active.
5. Cancel your old policy. Once the new policy is active, contact your old insurer to cancel. You may have a brief overlap period where you pay premiums on both policies, but this small cost is worth the protection of never having a gap in supplemental coverage.

When you have guaranteed-issue rights for Medigap

Under federal law, you have guaranteed-issue rights to buy a Medigap policy (meaning no medical underwriting) in these situations:

• Your Medicare Advantage plan leaves Medicare or stops providing care in your area
• You moved out of the plan's service area
• Your Medigap insurer committed fraud or misrepresented information in your policy
• You dropped your Medigap policy to join a Medicare Advantage plan for the first time and want to switch back within 12 months (trial right)
• Your Medicare SELECT plan's network no longer provides access to care in your area

Some states — including California, Connecticut, Maine, Massachusetts, Missouri, New York, Oregon, and Washington — have additional state-level protections that provide broader guaranteed-issue rights or annual open enrollment periods for Medigap. Check with your State Insurance Department for the rules that apply where you live.

What to Watch For When Switching Plans

Switching Medicare plans is not as simple as picking a new plan and calling it a day. There are several traps that catch people off guard. Here is what to watch for.

Coverage gaps

When switching between Medicare Advantage plans or between Advantage and Original Medicare, there should be no gap in coverage. Your old plan stays active until the new coverage starts. However, problems can occur if you cancel a Medigap policy before your new coverage is in place, or if you disenroll from a plan mid-year without an SEP. Always verify your new plan's effective date before letting go of any existing coverage.

Medical underwriting for Medigap

This is the number one issue that surprises people. If you leave Original Medicare and Medigap to join a Medicare Advantage plan, and then later decide you want to come back to Original Medicare, you may not be able to get a Medigap policy — or you may be charged significantly more. Outside of your initial Medigap Open Enrollment Period and specific guaranteed-issue situations, insurers in most states can deny you coverage based on health conditions like diabetes, heart disease, cancer history, or COPD.

Waiting periods and pre-existing condition limitations

If you are approved for a new Medigap policy outside of your open enrollment period, the insurer may impose a waiting period of up to six months during which they will not pay for treatment related to pre-existing conditions. However, if you had continuous creditable coverage with no gaps of 63 days or more before the new policy, the waiting period may be reduced or eliminated. This is another reason to never let your existing coverage lapse before the new policy is active.

Provider networks

If you are switching between Medicare Advantage plans, verify that all of your doctors, specialists, and preferred hospitals participate in the new plan's network before you enroll. Networks can vary significantly between plans from the same insurer. A provider who is in-network with a UnitedHealthcare HMO in your area might not be in-network with a different UnitedHealthcare PPO. Check the plan's provider directory and call your doctors' offices to confirm they accept the specific plan.

Drug formulary changes

When switching to a new plan that includes drug coverage, check that all your prescriptions are on the new plan's formulary. Look at the specific tier, any quantity limits, prior authorization requirements, and step therapy protocols. A medication that costs you $10 a month on your current plan could cost $95 on a new plan if it is placed on a higher formulary tier.

Losing progress toward out-of-pocket maximums

If you switch plans during the OEP (January 1 to March 31), any out-of-pocket spending you accumulated under your old plan in January, February, or March does not transfer to your new plan. Your deductible and MOOP counter reset to zero. This could matter if you had a hospitalization or major procedure early in the year. Consider whether it makes sense to wait until the next AEP instead.

Using the Medicare Plan Finder Tool

The Medicare Plan Finder at medicare.gov/plan-compare is the most important tool available when switching plans. It is free, maintained by CMS, and provides the most accurate and up-to-date information about every Medicare Advantage plan, Part D plan, and Medigap policy available in your area.

To get the best results from the Plan Finder:

• Log in with your Medicare account. This allows the tool to auto-populate your current drug list and coverage information, saving you time and improving accuracy.
• Enter every medication you take. Include dosage and frequency. The tool calculates your estimated annual drug costs for each plan based on this information.
• Add your preferred pharmacies. Drug costs vary by pharmacy. Adding your preferred pharmacy lets the tool show you the most accurate cost estimates.
• Sort by estimated total annual cost, not just premiums. A $0 premium plan with high copays could cost you more overall than a plan with a $50 monthly premium but lower cost-sharing. The Plan Finder gives you estimated total costs that account for premiums, deductibles, copays, and drug costs.
• Check star ratings. CMS rates every plan on a scale of 1 to 5 stars. Plans with 4 or 5 stars tend to have better outcomes, higher member satisfaction, and fewer complaints. This rating is an objective quality measure worth considering alongside cost.

You can also get personalized help by calling 1-800-MEDICARE (1-800-633-4227), contacting your local State Health Insurance Assistance Program (SHIP), or working with a licensed Medicare insurance agent who can walk you through the comparison process at no cost to you.

Frequently Asked Questions

Can I switch Medicare plans at any time during the year? No. You can only switch plans during designated enrollment periods. The main windows are the Annual Election Period (October 15 to December 7), the Medicare Advantage Open Enrollment Period (January 1 to March 31, only for current MA enrollees), and Special Enrollment Periods triggered by qualifying life events. Outside these windows, you are locked into your current plan.

Will I have a gap in coverage when I switch Medicare Advantage plans? No. When you enroll in a new Medicare Advantage plan, your old plan stays active until the effective date of the new plan. There is no overlap or gap. If you switch during the AEP, the new plan starts January 1 and the old one ends December 31. If you switch during the OEP, the new plan starts the first of the following month and the old plan terminates the day before.

What happens to my Medigap policy if I switch to Medicare Advantage? You will need to cancel your Medigap policy manually — it is not automatically terminated when you join an Advantage plan. Be aware that if you later decide to return to Original Medicare, you may not be able to get Medigap coverage again at the same rate or at all, depending on your health status and your state's rules. Some states offer a trial right that lets you return to your Medigap plan within 12 months if it is your first time trying Medicare Advantage.

Can I switch from Medicare Advantage back to Original Medicare and get a Medigap plan? You can always return to Original Medicare during the AEP or OEP. The challenge is getting a Medigap policy. Unless you have guaranteed-issue rights (such as the 12-month trial right for first-time Advantage enrollees, or your plan leaving Medicare), insurers in most states can use medical underwriting. If you have health conditions, you may be denied or charged a much higher premium. A few states — including New York, Connecticut, and Massachusetts — require guaranteed issue for Medigap year-round.

Do I need to call my old plan to cancel when I switch to a new Medicare Advantage or Part D plan? No. When you enroll in a new Medicare Advantage plan or Part D plan, your old plan is automatically disenrolled by CMS. You do not need to contact your old plan to cancel. The one exception is Medigap: you must contact your Medigap insurer directly to cancel that policy, because Medigap operates outside the CMS enrollment system.

How many times can I switch plans during the Medicare Advantage Open Enrollment Period? You can only make one change during the OEP (January 1 to March 31). Once you switch to a new Advantage plan or disenroll from Advantage back to Original Medicare, that decision is final for the rest of the OEP. You will not be able to make another change until the next Annual Election Period in the fall.

I just moved to a new state. Can I switch Medicare plans outside of the AEP? Yes. Moving out of your plan's service area triggers a Special Enrollment Period. You typically have two months from the date of your move to enroll in a new Medicare Advantage plan, Part D plan, or Medigap policy available in your new location. Make sure to notify Medicare and begin shopping for plans in your new area as soon as possible.

Is there a fee or penalty for switching Medicare plans? No. There is no fee or penalty for switching plans during a valid enrollment period. You will not be charged a cancellation fee by your old plan. However, if you drop Part D coverage and go more than 63 consecutive days without creditable drug coverage, you will face a late enrollment penalty when you eventually re-enroll in Part D. That penalty is permanent and is added to your monthly premium for as long as you have Part D coverage.

The Bottom Line

Switching Medicare plans is your right as a beneficiary, and it is something you should consider doing every year as plans change their costs, networks, and benefits. The process itself is not complicated — in most cases, enrolling in a new plan automatically disenrolls you from the old one, and there is no gap in coverage.

The key is timing. Know which enrollment period applies to your situation, start your research early, and use the Medicare Plan Finder to make side-by-side comparisons. Pay attention to the total picture — premiums, deductibles, copays, drug costs, provider networks, and star ratings — rather than making a decision based on any single factor.

The one area that demands extra caution is Medigap. Because of medical underwriting, leaving a Medigap policy is a decision that can be very difficult — and sometimes impossible — to reverse. If you are considering a move from Original Medicare with Medigap to a Medicare Advantage plan, understand the implications before you make the switch.

If you are unsure about any part of this process, reach out to a licensed Medicare insurance agent, call 1-800-MEDICARE, or contact your local SHIP counselor. These resources are free, and they can walk you through the options available in your specific area. The worst thing you can do is nothing — because a plan that is wrong for you will cost you more every year you keep it.