Updated: July 22, 2026
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MedMutual Protect has the lowest Plan F and Plan N rates while LifeShield National offers South Dakota's cheapest Plan G.
South Dakota's Medicare Supplement premiums range from $77 to $333 per month, depending on plan type.
Shop multiple carriers and evaluate plan restrictions, benefits and availability to find your best fit.
LifeShield National has the lowest Plan G premium at $145 per month. MedMutual Protect has the lowest prices for Plan N at $102 and Plan F at $165. Plan F costs $137 more per month than Plan N on average.
Fewer than a dozen carriers price plans for 65-year-olds in South Dakota. All but Transamerica use Attained Age pricing, which raises premiums as you age. Transamerica's Issue Age pricing locks your rate at the age you enroll, at $173 per month for Plan G.
| Farm Bureau Insurance | A | $88 | $196 | Attained Age Pricing |
| Humana | B | $178 | $88 | Attained Age Pricing |
| Globe Life | C | $229 | $98 | Attained Age Pricing |
| Philadelphia American | D | $139 | $51 | Attained Age Pricing |
| MedMutual Protect | F | $165 | $168 | Attained Age Pricing |
| LifeShield National | G | $145 | $126 | Attained Age Pricing |
| Transamerica | K | $77 | $30 | Issue Age Pricing |
| Transamerica | L | $115 | $58 | Issue Age Pricing |
| Transamerica | M | $141 | $0 | Issue Age Pricing |
| MedMutual Protect | N | $102 | $94 | Attained Age Pricing |
*Prices are for 65-year-olds.
The spread between the cheapest and most expensive plan is $152 per month. The difference between Plan K and Plan F, adds up to $1,056 per year.
LifeShield National's $145 covers the Part B deductible with no further exposure and its $126 gap below the statewide Plan G average is the widest price advantage of any carrier.
If you're in good health and rarely see specialists, MedMutual Protect's Plan N at $102 is the sharper pick, the $43 monthly difference versus Plan G buys flexibility if your health stays stable.
Average Plan G Rate
Plan Types
Average Plan G Rate
Plan Types
Average Plan G Rate
Plan Types
Average Plan G Rate
Plan Types
Average Plan G Rate
Plan Types
Average Plan G Rate
Plan Types
Average Plan G Rate
Plan Types
Among Plan G options in South Dakota, LifeShield National has the lowest monthly cost at $145. MedMutual Protect and Avera Health Plans also price Plan G below many competitors.
| LifeShield National | $145 | $126 | $1,740 | $1,509 |
| MedMutual Protect | $147 | $124 | $1,764 | $1,485 |
| Avera Health Plans, Inc. | $151 | $120 | $1,812 | $1,437 |
| Farm Bureau Insurance | $154 | $117 | $1,848 | $1,401 |
| USAA | $158 | $113 | $1,896 | $1,353 |
| Nassau | $159 | $112 | $1,908 | $1,341 |
| AFLAC | $163 | $108 | $1,956 | $1,293 |
South Dakota's Plan G spread range from $18 from cheapest to seventh-cheapest carrier, $145 at LifeShield National to $163 at AFLAC. Higher-spread states see gaps of $40 to $60 for identical coverage. Transamerica's Issue Age Plan G is at $173. LifeShield's $145 Attained Age plan costs $28 less now but rises each year.
MedMutual Protect has the lowest Plan F rate in South Dakota at $165 per month, 50% below the statewide average of $333. LifeShield National charges $175 and Nassau charges $193. Across carriers and deductible choices, Plan F premiums in the state run from $165 up to $236 each month, depending on pricing style and plan design.
| MedMutual Protect | $165 | $168 | $1,980 | $2,022 |
| LifeShield National | $175 | $158 | $2,100 | $1,902 |
| Nassau | $193 | $140 | $2,316 | $1,686 |
| AFLAC | $193 | $140 | $2,316 | $1,686 |
| American Benefit | $210 | $123 | $2,520 | $1,482 |
| Globe Life | $230 | $103 | $2,760 | $1,242 |
| Philadelphia American | $236 | $97 | $2,832 | $1,170 |
Plan F is only available to beneficiaries who enrolled in Medicare Part B before January 1, 2020. The $10 monthly gap between the cheapest ($165) and the second-cheapest ($175) means getting one additional quote saves up to $120 per year. Philadelphia American's $236 rate is the highest in MoneyGeek's South Dakota rate analysis.
MedMutual Protect has the lowest Plan N rate in South Dakota at $102 per month, with Farm Bureau close behind at $112. Plan N premiums in the state range from $102 to $132 per month.
| MedMutual Protect | $102 | $94 | $1,224 | $1,128 |
| Farm Bureau Insurance | $112 | $84 | $1,344 | $1,008 |
| LifeShield National | $113 | $83 | $1,356 | $996 |
| AFLAC | $115 | $81 | $1,380 | $972 |
| Nassau | $121 | $75 | $1,452 | $900 |
| American Benefit | $123 | $73 | $1,476 | $876 |
| Globe Life | $132 | $64 | $1,584 | $768 |
Plan N requires copays of up to $20 for doctor visits and up to $50 for emergency room visits that don't result in admission. The $30 monthly gap between MedMutual's $102 and Globe Life's $132 represents $360 per year. Beneficiaries who see a primary care doctor fewer than four times a year and have no chronic conditions usually come out ahead with Plan N over Plan G.
Finding your best Medicare Supplement plan depends on age and plan type. Compare rates using the filterable table below.
| Farm Bureau Insurance | A | No | 65 | $88 | $0 | Attained Age Pricing |
| Avera Health Plans, Inc. | A | No | 65 | $114 | $0 | Attained Age Pricing |
| Globe Life | A | No | 65 | $126 | $0 | Attained Age Pricing |
| Philadelphia American | A | No | 65 | $133 | $0 | Attained Age Pricing |
| Mutual of Omaha | A | No | 65 | $136 | $0 | Attained Age Pricing |
| State Farm | A | No | 65 | $143 | $0 | Attained Age Pricing |
| LifeShield National | A | No | 65 | $144 | $0 | Attained Age Pricing |
| United American | A | No | 65 | $147 | $0 | Attained Age Pricing |
| USAA | A | No | 65 | $151 | $0 | Attained Age Pricing |
| MedMutual Protect | A | No | 65 | $157 | $0 | Attained Age Pricing |
For 65-year-olds in South Dakota, Medicare Supplement premiums average $229 per month. Across the 10 standardized plan letters, monthly prices range from $107 for the lowest-cost option to $333 for the highest, with Plan K at the bottom of that range and Plan F at the top.
| A | $284 | $3,408 |
| B | $266 | $3,192 |
| C | $327 | $3,924 |
| D | $190 | $2,280 |
| F | $333 | $3,996 |
| G | $271 | $3,252 |
| K | $107 | $1,284 |
| L | $173 | $2,076 |
| M | $141 | $1,692 |
| N | $196 | $2,352 |
Plan G averages $271 per month. Plan N is $75 less at $196, and Plan F, available only to beneficiaries who enrolled before 2020, averages $333. Annual premiums across all 10 plan types range from $1,284 to $3,996.
Once you select your plan letter, compare South Dakota insurers that sell it. Evaluate companies on factors that affect your long-term costs and service quality.
Do you travel frequently? How often do you see doctors? More coverage costs more monthly but saves you money when you need care. If you have ongoing medical conditions requiring regular treatment, higher monthly premiums often cost less overall through lower out-of-pocket costs.
Plan G is the right starting point for most new Medicare beneficiaries. It covers all out-of-pocket costs except the Part B deductible. Plan N averages $75 less per month in South Dakota than Plan G. The tradeoff is copays: up to $20 per doctor visit and up to $50 for emergency room visits. Plan F covers everything including the Part B deductible. It's only available to beneficiaries who enrolled in Medicare Part B before January 1, 2020. Plans K and L are the cost-sharing options: lower monthly premiums with an annual out-of-pocket limit. Plans A, C and D each cover a different subset of Medicare cost-sharing with varying monthly costs.
Get quotes from at least three companies. Insurers charge different rates for identical coverage.
Three pricing methods exist. Issue Age pricing locks your premium at your enrollment age. Attained Age pricing rises as you get older, which can make a lower starting rate more expensive over time. Community-Rated pricing charges the same amount regardless of age. In South Dakota, only Transamerica uses Issue Age pricing. No community-rated plans are available in the state.
AM Best financial ratings tell you whether a carrier can pay claims over the long term. MoneyGeek's scoring weighted plan availability and affordability, but a carrier rated below A by AM Best warrants caution regardless of its rate. MedMutual Protect, Humana and Transamerica each carry an A (Excellent) AM Best rating.
Enroll during the six-month window starting when you turn 65 and sign up for Medicare Part B. You're guaranteed acceptance regardless of health conditions. Wait longer, and insurers may charge more or deny coverage.
South Dakotans shopping for Medigap coverage can use these resources:
For most South Dakota beneficiaries enrolling at 65 in 2026, Plan G from LifeShield National at $145 per month is the right default. It covers all out-of-pocket costs except the Part B deductible, and its rate is $126 below the statewide Plan G average. MedMutual Protect's Plan N at $102 is the better choice for healthy beneficiaries who see a doctor fewer than four times a year, the $43 monthly savings adds up to $516 per year.
The only carrier offering all 10 standardized plan types in South Dakota is Transamerica. Its Issue Age pricing is the right structure for beneficiaries who plan to hold their policy for a decade or more and want a rate that won't climb as they age. Buyers who want the lowest rate should start with LifeShield National's Plan G at $145 or MedMutual Protect's Plan N at $102.
We answer common questions about Medigap coverage for South Dakota residents.
Medicare Supplement open enrollment in South Dakota begins when you turn 65 and enroll in Medicare Part B. This six-month window guarantees coverage regardless of health conditions. You can buy a Medicare Supplement plan anytime, but insurers can deny coverage or charge higher rates outside this period.
Plan G, Plan F and Plan N are the most popular Medicare Supplement plans. Plan G covers all Medicare out-of-pocket costs except the Part B deductible. Plan F provides the most complete coverage but is available only to those eligible before 2020. Plan N has lower premiums than Plan G, with copayments of $20 for doctor visits and $50 for emergency room visits. Learn more about Medicare coverage.
No. Medicare Supplement plans automatically renew as long as you pay premiums on time. Your coverage continues indefinitely without annual enrollment periods, unlike Medicare Advantage plans that require yearly review during open enrollment.
Medicare Supplement plans work with Original Medicare to cover out-of-pocket costs like deductibles and copayments. Medicare Advantage plans replace Original Medicare entirely. They use different provider networks and cost structures with distinct coverage rules. Supplement plans offer more provider flexibility. Advantage plans often include extras like dental and vision coverage.
MoneyGeek collected South Dakota Medicare Supplement rates for 65-year-olds and 75-year-olds from Medicare.gov's plan browsing tool in May 2026, pulling data across all available carriers and plan letters in the state.
We scored South Dakota Medigap companies across three categories to create a weighted score out of 5:
About Mark Fitzpatrick
Mark Fitzpatrick, a licensed Property and Casualty (P&C) Insurance Producer in Connecticut, is MoneyGeek's resident insurance expert. He has spent nearly a decade analyzing the market, first at LendingTree and now at MoneyGeek, where he produces original research on hundreds of carriers and millions of rates across auto, home, renters, health and life insurance.
He covers economics and insurance at MoneyGeek, and his work has been featured in The Washington Post, The New York Times and NPR, among other outlets.
Like all MoneyGeek analysts, he draws on independent cost and consumer experience data. No insurance company partnership influences his recommendations.
Mark holds a B.A. from Boston College and an M.A. in Economics and International Relations from Johns Hopkins University. He started his career in financial risk management at State Street and is also a five-time “Jeopardy!” champion.
