Best Medicare Supplement Plans in Colorado (2026)

Colorado Medigap pricing follows federal standardization rules, which means Plan G from Transamerica covers exactly the same benefits as Plan G from State Farm or any other carrier. Every price difference you see on this page is purely the result of the insurer's pricing model and internal cost structure, not coverage quality. 

Colorado insurers price Medigap through one of two methods. Issue Age Pricing sets your premium based on how old you are when you first enroll, and that rate increases only for inflation. Premiums under Attained Age Pricing rise every year. For a 65-year-old enrolling today, an Attained Age plan often looks cheaper up front. Over 10 to 15 years, it usually costs more.

Transamerica has the best rates for Plan K at $87 per month, Plan L at $130 per month and Plan M at $160 per month. USAA provides Plan A coverage at $105 per month, while Wisconsin Physicians Service offers Plan C and State Farm has Plan D options. MedMutual Protect covers Plans F and N. Old Surety covers Plan G.

The $54 monthly gap between Transamerica's Plan B rate and the Colorado average is one of the pricing advantages we found across plan categories. For Plan K, the $16 monthly savings matters less at the outset, but Transamerica's Issue Age Pricing locks that rate in at enrollment. Attained Age carriers in the same category will cost more within a few years of enrollment for most Colorado seniors.

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

If your priority is keeping monthly costs low over time, start with Transamerica's Plan K at $87 per month. You'll pay more out of pocket when you use care, but the Issue Age rate locks in at enrollment. An Attained Age carrier at the same price today will likely cost more than Plan G from a community-rated carrier by the time you're 75.

Plan G is the right choice for comprehensive coverage with no surprise bills. Old Surety's $163 rate is the lowest in Colorado for Plan G. But Old Surety's lineup covers only three plan types. State Farm's six-plan lineup at $175 for Plan G gives more room to move for enrollees who want to change plans later without switching carriers.

Plan G rates in Colorado run from $163 at Old Surety to $179 at Anthem, Bankers Life and Wellcare for 65-year-olds. Plan G rates in Colorado run from $163 at Old Surety to $179 at Anthem, Bankers Life and Wellcare for 65-year-olds.

Old Surety, LifeShield National and Atlantic Capital all price within $3 of each other at the low end of Colorado's Plan G market. For most Colorado enrollees shopping Plan G, the practical decision is in $163 to $168 range. Check each carrier's financial strength rating. Identical plan benefits mean service and financial stability are the tiebreakers.

For 65-year-olds in Colorado, Medicare Supplement plan costs range from $103 to $341 per month, depending on which plan you choose.

Plan G averages $282 per month and is the most popular option in the state. Plan N costs $242 and attracts enrollees who want broad coverage at a lower monthly rate. On the lower end, Plan K starts at $103, Plan M runs $160 and Plan L is $173 per month. Plan C is the highest at $341.

The $179 monthly gap between Plan K at $103 and Plan G at $282 is the sharpest trade-off in the Medigap market here. Plan K is cheaper because you share more costs when you use care. Plan G costs $2,148 more per year in premiums but covers everything except the Part B deductible. Plan G and Plan N are $40 apart per month. Plan N requires small copays at some doctor visits, so the right choice between the two depends on how often you see specialists.

Choose your plan type based on how much cost-sharing you want, then compare carriers within that type on price. Every Plan G in Colorado covers the same benefits regardless of insurer, so price and carrier financial strength are the only variables.

Learn More: What Does Medicare Cover and Not Cover?

Start with the NAIC Consumer Insurance Search tool to check complaint ratios for any carrier you're considering. Then compare Plan G quotes from carriers in the $163 to $168 range.  Financial strength and pricing structure shape what you pay every month. Customer service reputation matters most when you need to use your coverage.

For most Colorado seniors enrolling at 65, the right starting sequence is: choose your plan type first, then compare carriers within that type on price and financial strength. Plan G from a carrier in the $163 to $168 range covers the most ground. If budget is the primary constraint, Plan K from Transamerica at $87 per month is the lowest available rate in the state.

Colorado residents seeking Medicare Supplement guidance can connect with these statewide organizations:   

• State Health Insurance Assistance Program (SHIP): Colorado's SHIP program sits within the Division of Insurance and maintains 17 counseling locations statewide. Volunteers answer questions about Medicare enrollment, Part D plans, Medigap policies, and Medicare Advantage options. SHIP counselors explain premium costs, deductibles, and coverage differences between plan types. Spanish speakers can reach Colorado SHIP at (866) 665-9668. Main line: (888) 696-7213.
• Colorado Division of Insurance: Files complaints through a secure Consumer Portal where policyholders track case status and communicate directly with investigators. The division publishes annual complaint ratios and indices showing how each insurer compares to industry averages. Complaint index scores above 1.0 indicate higher-than-average complaint levels per premium dollar. Phone help at (303) 894-7490. Choose Option 2 for health insurance questions. Email: DORA_Insurance@state.co.us.
• Colorado Area Agencies on Aging: Sixteen regional agencies serve all 64 Colorado counties with programs for adults 60 and older. Services include options counseling, case management, nutrition programs, caregiver support, and long-term care ombudsman advocacy. Agencies work with individuals to create personalized plans for staying independent. Contact your county's agency through the C4A website or call the State Unit on Aging at (303) 866-2800.
• Medicare.gov: Enter your ZIP code to see every Medicare Supplement plan sold in your area, sorted by monthly premium. Filter results by coverage level, company rating, and extra benefits.

Frequently asked questions about Medigap coverage in Colorado are answered below.

MoneyGeek collected rate data for all 10 standardized Medicare Supplement plan types in Colorado, covering carriers available to 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 Colorado based on three main categories to create a weighted score out of 5:

• Affordability (50%): The lowest monthly cost earns the highest score in this category.
• Pricing style (20%): Medigap insurers use three pricing methods: Community Pricing, Issue-Age Pricing and Attained Age Pricing. Community Pricing scores highest at 1.0. Issue-Age Pricing follows at 0.8, with Attained-Age Pricing at 0.6 because it exposes enrollees to annual premium increases. A slightly higher-cost community-rated plan can still outscore a cheaper attained-age plan because premiums stay more stable over time.
• Plan availability (30%): A wider plan selection earns a higher score. Plans G, F and N carry additional weight because they are the most commonly chosen.