Medicare Supplement (Medigap) plans in Indiana

Medicare Supplement insurance — usually called Medigap — is private coverage that pairs with Original Medicare (Parts A and B). Instead of replacing Medicare, it fills the gaps: the deductibles, copayments and coinsurance you’d otherwise pay yourself. You then add a standalone Part D drug plan for prescriptions. The Indiana Department of Insurance regulates the policies; the benefits inside each plan letter are set federally.

How Medigap is different from Advantage

The plans Hoosiers actually buy

Plan G covers everything Original Medicare leaves behind except the Part B deductible ($283 in 2026). Plan N costs less in exchange for small office and emergency copays and no coverage of Part B excess charges. High-deductible Plan G has a much lower premium and a deductible you pay first. Plan F still exists for people who were eligible before 2020 but cannot be sold to anyone newer. Because benefits are standardized, we compare companies on price and on how fast they have raised it.

When you can buy one without health questions

• Your six-month open enrollment. It starts the month you are 65 or older and enrolled in Part B. During it, every plan a company sells is guaranteed available regardless of health.
• The Indiana birthday rule, every year after that. If you are 65 or older and already hold a Medigap policy, each year you can apply to another insurer for the same plan letter (including its variations, such as high-deductible G) without underwriting. The window opens 31 days before your birthday and closes 31 days after it, and the new policy takes effect the first day of the month after you sign the application. The rule came in as HEA 1226 of 2025 and was amended by HEA 1260 of 2026, which applies to policies delivered, issued or renewed on or after March 15, 2026. It is a switching rule, not a first-purchase rule: you need to be in a Medigap policy already.
• Under 65 on disability or ESRD. Since January 1, 2025, Indiana Code 27-8-13-9.1 (SEA 215) gives people under 65 who are enrolled in Medicare their own six-month guaranteed-issue window when Part B begins, requires insurers that sell Medigap at 65 to offer it to them, and limits what they can be charged for Plans A, B and D. A second open enrollment for every plan still arrives at 65.
• Guaranteed-issue events. Losing an Advantage plan or employer coverage through no fault of your own gives you a window (generally 63 days) to buy certain plans without underwriting.
• Outside those windows, Indiana insurers can use medical underwriting. Moving from Advantage to Medigap after the first year, for example, usually means answering health questions.

Compare the rate history, not just the first-year price

Because the benefits are standardized, the only real differences between Indiana Medigap companies are what they charge and how steeply they raise it later. That second part is public: every carrier files its rate increases with the Indiana Department of Insurance, and a policy that looks cheap at 65 can be the expensive one by 75. We publish that filing history on our research site, Indiana Medigap rate history, with each figure tied to the filing it came from. If your premium has already gone up and you want to know why, why Medigap premiums increase covers the three causes — and with the birthday rule, the answer in Indiana is now “shop it in your window,” not “live with it.”

Who Medigap tends to suit

People who want maximum freedom to choose doctors and hospitals — IU Health and Ascension St. Vincent without a network question, a specialist across the river in Louisville or up the road in Chicago — predictable costs, and coverage that travels. That last point is why so many Hoosier snowbirds keep a supplement. The cost is a monthly premium that rises with age and with the carrier’s filings, which the birthday rule now lets you answer.