Medicare Supplement Insurance, often called Medigap, helps with certain costs left by Original Medicare. The opportunity to buy or change a Medigap policy is a separate issue from choosing a Medicare Advantage or drug plan. Check the right that applies to you before canceling existing coverage.
Which enrollment protection applies?
The federal Medigap Open Enrollment Period generally begins in the first month you are 65 or older and enrolled in Part B, and lasts six months. Outside that period, your ability to buy a policy or the price offered may depend on underwriting unless a specific protection applies. State rules can provide additional rights. People under 65 may have different options; do not assume every state or insurer offers the same access.
Certain situations create guaranteed-issue or trial rights, but each has conditions, deadlines and eligible policies. The words alone are not proof that a particular application qualifies. Medicare's situation-based tool and your state insurance department can help identify the applicable rule.
| Before changing coverage | What to confirm in writing |
|---|---|
| Current coverage | The type of policy or Medicare plan you actually have |
| Claimed protection | The enrollment, guaranteed-issue or trial-right basis |
| Deadline | The start and end of the relevant application period |
| Policy availability | Which policy is available in your state and circumstances |
| Effective dates | How the old and new coverage dates will fit together |
| Evidence | Which notices the insurer needs through its approved channel |
This checklist should expose missing answers before a cancellation. Put a question mark beside an unconfirmed right rather than treating a quote or a general explanation as an approval.
A Medicare plan change is not a Medigap approval
Medigap cannot be used to pay Medicare Advantage premiums or cost sharing. Returning to Original Medicare does not automatically establish a right to buy any Medigap policy. Medicare also notes that most Medigap policies do not automatically cancel when someone joins an Advantage plan; ask the insurer about the actual cancellation process and consequences.
Medigap policies sold after 2005 do not include prescription drug coverage. Use the Part D coverage worksheet to keep that decision visible. Compare overall arrangements in the Original Medicare and Advantage guide.
Your next step is to verify your specific rights with Medicare, your state insurance department, SHIP and the insurer before changing coverage. Keep applications and health information in their secure channels. This guide neither promises acceptance nor determines underwriting or state eligibility.
Browse federal benefits, retirement and insurance topics or read how we prepare and check our guides.
Sources
- Medicare: Buying a Medigap policy, checked November 4, 2026
- Medicare: How Medigap works, checked November 4, 2026
- Medicare: When can I buy Medigap?, checked November 4, 2026
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