Best Medicare Supplement Plans in Illinois (2026)

Our analysis of Medicare Supplement providers in Illinois found monthly premiums ranging from $96 to $208 for seniors aged 65 across 10 standardized plan types. These affordable Medigap plans provide strong financial protection while keeping costs manageable for Illinois residents.

MedMutual Protect offers the best rates across three popular plans: Plan N at $101 monthly, Plan G at $144 monthly and Plan F at $164 monthly, while USAA has the lowest Plan A rates. Illinois beneficiaries choosing these insurers save $21 to $155 monthly compared to average state rates.

*These rates reflect Medigap premiums for 65-year-olds.

Everyone's coverage needs are different, so your best option may differ from these popular choices. Explore the table below to find the Illinois Medicare Supplement company that matches your specific situation.

Illinois residents age 65 pay $117 to $319 monthly for Medicare Supplement insurance depending on plan type. Monthly costs vary by $202 between the cheapest and most expensive plans. 

Plan K costs $117 monthly, the lowest average rate while Plan F costs $319 monthl, the highest average. Plan G averages $253 monthly. Additional options include Plan M at $145, Plan L at $182 and Plan D at $225 monthly.

Federal law standardizes Medicare Supplement plans. Plan G from Company A covers exactly what Plan G from Company B covers, meaning premium amounts vary while benefits stay the same across insurers. Compare what each plan type covers to choose the right balance between premiums and out-of-pocket expenses.

Learn More: What Does Medicare Cover and Not Cover?

Your Medicare Supplement insurer selection should focus on cost differences, service quality and company reliability as the benefits are identical for all plan types.

Illinois residents comparing Medigap plans can access these resources: 

• Senior Health Insurance Program (SHIP): Free statewide health insurance counseling for Medicare beneficiaries and caregivers through Illinois Department on Aging. Trained volunteers and certified counselors meet one-on-one for confidential sessions. SHIP produces annual Medicare Supplement Premium Comparison Guides. Senior HelpLine: 1-800-252-8966 (TTY: 1-888-206-1327). Email: aging.ship@illinois.gov. SHIP counselors educate about Medicare Parts A and B, Medicare Supplements, Medicare Advantage plans and Part D prescription drugs.
• Illinois Department of Insurance - Consumer Services: File complaints online or request forms through Consumer Assistance Hotline: 866-445-5364. Written complaints required. Illinois law gives insurers 21 days to respond. Investigations take four to six weeks. Complaints remain confidential records. Mail to 320 W. Washington Street, Springfield, IL 62767. Chicago office: 115 S. LaSalle Street, 13th Floor, Chicago, IL 60603, (312) 814-2420.
• Illinois Area Agencies on Aging: Thirteen Planning and Service Areas covering Illinois' 102 counties, managed by 12 nonprofit corporations and Chicago's Department of Family and Support Services. Agencies contract with local organizations to provide senior services. Contact Senior HelpLine: 1-800-252-8966 for your local agency and available programs.
• Medicare.gov: Enter your ZIP code in the Plan Finder to browse Medigap policies sold in Illinois and examine coverage details side by side.

If you’re unsure how Medigap coverage works in Illinois, the answers below address common concerns.

MoneyGeek collected data for all Medicare plans in Illinois for 65-year-olds and 75-year-olds, using the plan browsing tool at Medicare.gov. Unless otherwise noted, the data in this article references quotes pulled for 65-year-olds in the state.

We scored Medigap companies in Illinois based on three main categories to create a weighted score out of 5:

• Affordability (50%): Providers with the lowest monthly cost score higher.
• Pricing style (20%): Medigap insurers use three methods to determine premiums: Community Pricing, Issue-Age Pricing and Attained Age Pricing. We gave higher scores for pricing styles that are more stable and equitable, as follows: Community Pricing 1.0, Issue-Age Pricing 0.8, Attained-Age Pricing 0.6. Using this scaling, a slightly higher-cost community-rated plan can still score higher overall than a cheaper but more volatile attained-age plan.
• Plan availability (30%): Providers with a wider range of plan types score higher, with weighted scoring given to the most popular plan types like Plan G, Plan F and Plan N.