Choosing the right Medigap insurer can save you thousands of dollars in out-of-pocket medical costs each year. If you are researching the 10 best supplemental insurance companies, you are already taking a smart step toward protecting your finances in retirement. With more than 70 insurers offering standardized Medigap plans across the country, narrowing the field to the strongest options requires looking at financial stability, premium pricing, customer service records, and claims processing speed.
How We Ranked the Best Supplemental Insurance Companies
Our rankings draw on data from AM Best financial strength ratings, the National Association of Insurance Commissioners (NAIC) complaint index, J.D. Power customer satisfaction surveys, and publicly available rate filings from state insurance departments. Every company on this list holds an AM Best rating of A- or higher, meaning independent analysts consider it financially stable enough to pay future claims.
We also weighted premium competitiveness, the number of states where the company sells policies, and whether it offers household or nonsmoker discounts. Plans themselves are standardized by federal law, so a Plan G from one company covers exactly the same benefits as a Plan G from another. That makes price, service, and reliability the deciding factors.
1. AARP / UnitedHealthcare
UnitedHealthcare underwrites the AARP Medicare Supplement Insurance Plans, making it the largest Medigap insurer in the United States by enrollment. The company operates in all 50 states plus the District of Columbia and offers Plans A, B, C, F, G, and N. Monthly premiums for Plan G typically range from $140 to $280 depending on age, location, and tobacco use.
AARP-branded plans include a fitness program, a 24/7 nurse hotline, and travel emergency coverage. The NAIC complaint index for UnitedHealthcare has remained near the national median in recent years, indicating average complaint volume relative to its massive market share.
2. Mutual of Omaha
Mutual of Omaha consistently ranks among the 10 best supplemental insurance companies thanks to competitive rates and strong financial backing. The company holds an A+ rating from AM Best and sells Medigap policies in 49 states. Plan G premiums often start around $120 to $230 per month for a 65-year-old, though rates vary by ZIP code.
Mutual of Omaha uses attained-age rating in most states, which means premiums increase as you get older. However, its starting rates tend to be lower than many competitors, and the insurer offers a household discount of up to 7 percent when two or more people in the same household hold policies.
3. Cigna
Cigna sells Medigap plans in more than 40 states and carries an A rating from AM Best. The company is known for straightforward enrollment and responsive claims processing. Plan N premiums from Cigna typically fall between $100 and $190 per month for new enrollees at age 65, making it one of the more affordable options for beneficiaries who prefer Plan N’s lower premium in exchange for modest copays.
4. Aetna
Aetna, now part of CVS Health, offers Medigap plans in most states and benefits from the financial strength of its parent company. AM Best assigns Aetna an A rating. Plan G rates generally range from $130 to $260 per month. Aetna also provides a SilverSneakers fitness benefit with many of its supplement plans, a perk that appeals to active retirees.
5. Blue Cross Blue Shield (Various Affiliates)
Blue Cross Blue Shield is not a single company but a federation of 34 independently operated affiliates. Several BCBS affiliates rank among the top Medigap sellers in their respective states. In states like Michigan, North Carolina, and Minnesota, BCBS affiliates often dominate the Medigap market with competitive premiums and extensive provider networks. Because Original Medicare allows you to see any provider that accepts Medicare, network size matters less for Medigap than for Medicare Advantage, but brand recognition and local customer service give BCBS affiliates an edge.
6. Humana
Humana offers Medicare Supplement plans in more than 30 states. The company holds an A- rating from AM Best and is widely recognized for its Medicare Advantage products, but its Medigap lineup is also competitive. Plan G premiums from Humana typically range from $135 to $250 per month. Humana frequently bundles its supplement plans with wellness resources and preventive care reminders.
7. State Farm
State Farm is better known for auto and home insurance, but the company also sells Medigap plans in many states. Its A++ AM Best rating is the highest available, reflecting exceptional financial strength. Plan G premiums from State Farm are mid-range, generally $140 to $270 per month for a 65-year-old. Existing State Farm policyholders may qualify for multi-policy discounts.
8-10. Bankers Fidelity, Manhattan Life, and GPM Health and Life
These three smaller carriers round out our list of the 10 best supplemental insurance companies. Bankers Fidelity operates primarily in the Southeast and offers some of the lowest Plan G rates in states like Georgia and Alabama, often starting below $120 per month. Manhattan Life serves more than 40 states and uses issue-age rating in several markets, which locks your base rate at the age you enroll. GPM Health and Life, part of the Stancorp family, offers competitive Plan N rates and has earned praise for fast claims turnaround.
Smaller insurers can offer lower premiums because they carry less overhead, but it is important to verify their AM Best rating and NAIC complaint ratio before enrolling. All three companies listed here hold AM Best ratings of A- or higher.
Factors to Consider When Choosing a Medigap Insurer
Because Medigap benefits are standardized, price and service quality should drive your decision. Pay attention to the company’s premium rating method. Insurers use one of three approaches: community-rated (everyone pays the same base rate regardless of age), issue-age-rated (your premium is based on your age at enrollment), or attained-age-rated (premiums rise as you age). Community-rated and issue-age-rated policies tend to cost more initially but grow more slowly over time.
Also look at available discounts. Many of the 10 best supplemental insurance companies offer nonsmoker discounts of 5 to 15 percent, household discounts, and annual payment discounts. Over a 20-year retirement, these savings add up significantly.
For a deeper look at which plan letter provides the best value, see our guide on Medicare Supplement Plan G and our comparison of Medicare Plan F vs Plan G.
How to Compare Quotes
The most efficient way to compare Medigap premiums is through your state’s insurance department website or the Medicare.gov plan finder tool. Enter your ZIP code, age, gender, and tobacco status to see current rates from every licensed insurer in your area. You can also work with an independent insurance broker who represents multiple carriers and can pull quotes side by side at no extra cost to you.
When comparing quotes, make sure you are looking at the same plan letter. A Plan G quote from one company should only be compared against Plan G quotes from others. For a broader overview of all plan letters and their benefits, visit our Compare Medicare Supplement Plans Guide and our Medigap Cost Comparison Chart.
Frequently Asked Questions
Are Medigap benefits the same regardless of the company?
Yes. Federal law requires that each Medigap plan letter (A, B, C, D, F, G, K, L, M, N) cover the same set of benefits no matter which company sells it. The only differences between insurers are price, customer service, and financial stability. This standardization is why comparing the 10 best supplemental insurance companies comes down to cost and reliability rather than coverage differences.
When is the best time to buy a Medigap policy?
Your best opportunity is during the Medigap Open Enrollment Period, which starts the month you turn 65 and are enrolled in Medicare Part B. During this six-month window, insurers cannot deny you coverage or charge higher premiums based on pre-existing conditions. After this period, companies in most states can use medical underwriting and may refuse to sell you a policy.
Can I switch Medigap companies later?
You can apply to switch at any time, but outside of your initial open enrollment period, the new insurer can require medical underwriting. Some states, such as California, Connecticut, and Missouri, offer annual open enrollment or birthday rules that give you guaranteed-issue rights to switch. Check with your state insurance department for local rules.
Do any of these companies offer Plan F?
Most major Medigap insurers still sell Plan F, but only to people who became eligible for Medicare before January 1, 2020. If you qualified for Medicare after that date, Plan G is the closest alternative. Learn more in our Medicare Plan F guide.
Making Your Final Decision
Start by identifying the plan letter that fits your healthcare needs and budget. Then pull quotes from at least three to five insurers in your area and verify each company’s AM Best rating and NAIC complaint index. If two companies offer similar premiums, lean toward the one with better customer satisfaction scores and a longer track record in the Medigap market. Finally, enroll during your Medigap Open Enrollment Period whenever possible to guarantee acceptance and the lowest available rate. For additional context on how supplemental plans fit into the broader Medicare landscape, explore our healthcare costs guide and our overview of Medigap vs Medicare Advantage.