Updated July 2, 2026
Illinois is one of the more competitive Medigap markets in the country. Dozens of carriers operate here, and the typical Plan G premium runs around $142 per month. With that much competition, the spread between carriers is worth your attention.
How Is a Medigap Premium Calculated in Illinois
Because Illinois has a large Medicare population and many competing insurers, you will find more plan options here than in smaller states. The coverage itself is identical across carriers: federal law standardizes Plan G benefits, so you are only comparing price and company reputation. That size of the Illinois market tends to keep premiums from getting too far out of line, but individual carriers still vary enough that comparing a few quotes can save you $20 to $40 a month. Start with the Medigap cost calculator for an estimate by age, and use the plan comparison if you are still deciding which letter plan fits your situation.
Enrolling in Illinois
Federal rules set the enrollment timeline. Your 6-month Open Enrollment Period starts the month your Medicare Part B goes into effect. During that window, no insurer in Illinois can decline you or add a surcharge for health conditions. After it closes, they can. The open enrollment calculator shows your window based on your Part B start date. Still comparing Medigap to Medicare Advantage? The Medigap vs Advantage calculator puts both options side by side so you can see which works out lower for your expected usage.
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FAQs
How much does Medigap Plan G cost in Illinois?
Plan G premiums in Illinois run around $142 a month for most new enrollees, though your exact rate depends on your age, sex, tobacco use and the insurer you choose.
Do all Plan G policies in Illinois cover the same things?
Yes. Federal law standardizes the benefits inside every Plan G, so a policy sold in Illinois covers exactly the same services no matter which carrier issues it. Only the premium and the rating method differ from one Illinois carrier to the next.