Medigap premiums for the exact same coverage can differ by $100 a month or more between insurers selling in the same zip code, and that gap only widens when you compare the richest plan (Plan G) against the leanest ones (Plan K, Plan L, and High-Deductible Plan G). Original Medicare sets the benefits every Medigap letter plan must cover, but private insurers set the price, so shopping matters as much as picking the right letter.
California, Texas, and every other state license their own set of Medigap carriers, and premiums are not federally regulated the way Medicare Part B premiums are. This guide breaks down which 2026 Medigap plans run cheapest, what you give up for the lower premium, and what to do if even the cheapest Medigap plan does not fit your budget. See also Medigap vs Medicare Advantage and is Medicare Supplement worth it.
Coverage Breakdown
Coverage by type| Medigap Plan | Average Monthly Premium (2026) | What You Pay in Cost-Sharing | Out-of-Pocket Limit or Deductible (2026) |
|---|
| Medigap Plan K | $70 to $140 a month (2026 estimate) | You pay 50% of Part A and Part B coinsurance, copays, and deductibles | $8,000 out-of-pocket limit; plan pays 100% after that (2026) |
| Medigap Plan L | $90 to $160 a month (2026 estimate) | You pay 25% of Part A and Part B coinsurance, copays, and deductibles | $4,000 out-of-pocket limit; plan pays 100% after that (2026) |
| High-Deductible Plan G | $45 to $130 a month (2026 estimate) | You pay 100% of Medicare-covered costs until the deductible is met | $2,950 annual deductible; plan pays 100% after that (2026) |
| Plan G (standard) | $150 to $230 a month (2026 estimate) | You pay only the annual Part B deductible; the plan covers the rest | $283 Part B deductible is your only exposure (2026) |
| Plan N | $120 to $200 a month (2026 estimate) | You pay small copays: up to $20 per office visit, up to $50 per ER visit | No separate out-of-pocket limit beyond copays and the Part B deductible (2026) |
Medigap premiums are set by private insurers, not the federal government, and vary by state, age, gender, tobacco use, and rating method (community-rated, issue-age-rated, or attained-age-rated). The ranges above are 2026 national estimates compiled from carrier rate filings; KFF's most recent verified snapshot put the average Plan G premium at $164 a month among 2023 policyholders, ranging from $140 in Washington, DC to $236 in New York, and 2026 carrier quotes generally run higher.
Source: Medicare.gov Medigap Plan Finder 2026, CMS CY2026 Medigap Deductible and Out-of-Pocket Limit Announcements, KFF Key Facts About Medigap Enrollment and Premiums
Direct Answer
It depends on your state, age, and insurer, but Medigap Plan K, Plan L, and High-Deductible Plan G are consistently the least expensive Medicare Supplement plans in 2026, with average premiums between $45 and $160 a month versus $150 to $230 for standard Plan G. The tradeoff is real: cheaper Medigap plans require you to pay 25 to 50 percent of Medicare-approved costs, or a $2,950 deductible, before the plan pays anything.
What Determines a Medigap Plan's Price
Original Medicare sets the benefits every Medigap letter plan must cover nationwide, so a Plan G bought in Ohio covers the exact same services as a Plan G bought in Florida. Private insurers set the premium, and the biggest driver of that premium is how much cost-sharing the plan absorbs on your behalf. Plans that pay close to 100% of Medicare's coinsurance, copays, and deductibles (Plan F for those eligible, Plan G, and Plan N) carry the highest monthly premiums because the insurer is taking on the most financial risk.
Plan K, Plan L, and High-Deductible Plan G flip that math: the insurer absorbs less risk because you agree to pay a percentage of costs (Plan K and Plan L) or a full deductible before coverage kicks in (High-Deductible Plan G), so the monthly premium drops in exchange. Rating method also matters. Community-rated states charge everyone in an area the same premium regardless of age; attained-age-rated states raise your premium every year as you get older, even on the same plan letter, which is why shopping again every few years can lower your cost.
The 3 Cheapest Medigap Plans in 2026: K, L, and High-Deductible G
Medigap Plan K pays 50% of Part A and Part B coinsurance, copays, and the Part A hospital deductible, and caps your total out-of-pocket spending at $8,000 in 2026; once you hit that limit, Plan K pays 100% of covered costs for the rest of the calendar year. Medigap Plan L works the same way but pays 75% of cost-sharing and caps your exposure at $4,000 in 2026, which explains why Plan L premiums run higher than Plan K even though both are considered budget plans.
High-Deductible Plan G takes a different approach: you pay 100% of Medicare-covered costs out of pocket, including the Part B deductible, until you reach the $2,950 annual deductible set by CMS for 2026, and then the plan pays like standard Plan G for the rest of the year. For a beneficiary in good health who rarely visits a doctor, High-Deductible Plan G often produces the lowest total annual cost of any Medigap letter, even after accounting for the deductible. Compare live quotes for all three plans through Medicare.gov's Medigap Plan Finder by zip code before you enroll.
What You Pay Without Any Medigap Plan in 2026
Original Medicare alone leaves real gaps in 2026: a $1,736 Part A deductible for each benefit period of hospitalization, a $283 Part B deductible before outpatient coverage starts, and a 20% Part B coinsurance on doctor visits, outpatient procedures, and durable medical equipment with no annual cap. A single hospital stay followed by months of physical therapy can push out-of-pocket costs into the thousands of dollars without any supplemental coverage, which is the core reason Medigap and Medicare Advantage exist.
Standard Medicare Part B premiums run $202.90 a month in 2026 regardless of which supplemental coverage you choose, so the Medigap premium is always an additional cost layered on top, not a replacement for it. Weighing a $45 to $160 monthly Medigap premium against thousands of dollars in uncapped 20% coinsurance is the real math most beneficiaries need to run.
Medicare Advantage as a Lower-Premium Alternative
Medicare Advantage plans frequently advertise $0 monthly premiums in 2026, which makes them look cheaper than even the leanest Medigap plan at first glance. The comparison is not apples to apples: Medicare Advantage plans use provider networks (HMO or PPO) and charge copays or coinsurance per visit instead of a flat monthly premium, and CMS caps in-network out-of-pocket spending at $9,250 in 2026 (or $13,900 combined in-network and out-of-network), well above what most Medigap plans expose you to.
The enrollment-weighted average in-network out-of-pocket maximum for Medicare Advantage actually lands around $5,421 in 2026, which can beat Medigap Plan K's $8,000 limit for beneficiaries who stay in-network and use care sparingly, but loses badly for anyone who needs out-of-network specialists or extensive care during the year. Medicare Advantage is worth comparing directly against Plan K, Plan L, and High-Deductible Plan G rather than against Plan G, since it competes on the same low-premium, higher-risk logic.
Medigap Eligibility and Enrollment Rules
Enrollment in Original Medicare Part A and Part B is required before you can buy any Medigap plan, including the cheapest ones. Your Medigap Open Enrollment Period is a one-time 6-month window that starts the month you turn 65 and are enrolled in Part B; during that window, insurers must sell you any Medigap plan they offer in your state at their best available rate, with no medical underwriting and no denial for preexisting conditions.
Outside that 6-month window, most states allow insurers to medically underwrite Medigap applications, meaning they can charge more, add a preexisting condition waiting period of up to 6 months, or deny coverage outright based on your health history. This is different from the Medicare Advantage Annual Enrollment Period (October 15 to December 7, 2026) or the Medicare Advantage Open Enrollment Period (January 1 to March 31, 2026), which apply to switching Medicare Advantage or Part D plans, not to buying Medigap. Use Medicare.gov's Medigap Plan Finder to compare every licensed insurer's rate for Plan K, Plan L, and High-Deductible Plan G in your zip code before you apply.
Alternatives if Medigap Premiums Don't Fit Your Budget
Beneficiaries who cannot afford even the cheapest Medigap plan have several documented paths to lower costs in 2026, all worth checking before giving up on supplemental protection entirely.
- Medicare Savings Programs: state Medicaid agencies run QMB, SLMB, and QI programs that pay your Part B premium and, for QMB, your Medicare cost-sharing too, for beneficiaries under specific income limits that vary by state.
- Full Medicaid for dual-eligible beneficiaries: about 12 million Americans qualify for both Medicare and Medicaid, and Medicaid can cover cost-sharing Medigap would otherwise charge a premium for, with no Medigap purchase needed.
- PACE (Program of All-Inclusive Care for the Elderly): coordinates and covers nearly all Medicare and Medicaid services for qualifying frail seniors who need a nursing-home level of care but want to stay at home, replacing the need for separate Medigap coverage.
- $0-premium Medicare Advantage: trades Medigap's flat premium for network restrictions and per-visit cost-sharing, worth comparing directly against Plan K and Plan L rather than against richer Medigap letters.
- State Health Insurance Assistance Program (SHIP): free, unbiased local counseling in every state to compare actual Medigap quotes, Medicare Advantage plans, and Medicare Savings Program eligibility side by side before you enroll.
Frequently Asked Questions
What is the cheapest Medigap plan in 2026?
High-Deductible Plan G is typically the cheapest, averaging $45 to $130 a month in 2026, followed closely by Plan K at $70 to $140 a month. Actual pricing depends heavily on your state, age, and whether you enroll during your 6-month Medigap Open Enrollment Period, when insurers cannot medically underwrite your application.
What is the difference between Medigap Plan K and Plan L?
Plan K pays 50% of Medicare's coinsurance, copays, and deductibles and caps your annual out-of-pocket spending at $8,000 in 2026. Plan L pays 75% of the same cost-sharing and caps your exposure at $4,000 in 2026. Plan L costs more per month because it covers a larger share of your bills before you hit the out-of-pocket limit.
Is High-Deductible Plan G a good deal in 2026?
For beneficiaries who rarely see a doctor, yes. You pay 100% of Medicare-covered costs, including the $283 Part B deductible, until you reach the $2,950 annual deductible set by CMS for 2026, then the plan pays exactly like standard Plan G for the rest of the year. Premiums average $45 to $130 a month, often $100 or more below standard Plan G.
Can Medicare Advantage be cheaper than Medigap?
Often, at least on premium: many Medicare Advantage plans charge $0 a month in 2026 versus $45 and up for the cheapest Medigap plan. But Medicare Advantage caps in-network out-of-pocket spending at up to $9,250 in 2026 and requires you to use a provider network, while Medigap Plan K and Plan L cap exposure lower, at $8,000 and $4,000 respectively, with no network restrictions.
When can I buy a Medigap plan without medical underwriting?
During your Medigap Open Enrollment Period, a one-time 6-month window starting the month you turn 65 and are enrolled in Part B. Insurers must sell you any plan they offer in your state at their best rate during that window, no health questions asked. Outside it, most states allow medical underwriting, which can raise your premium or get you denied.
What if I still can't afford any Medigap plan?
Check Medicare Savings Programs (QMB, SLMB, QI) through your state Medicaid agency, which can pay your Part B premium and cost-sharing based on income. If you qualify for full Medicaid as a dual-eligible beneficiary, you generally do not need to buy Medigap at all. A free SHIP counselor in your state can walk through every option with you.
Does the cheapest Medigap plan change by state?
Yes. Medigap premiums are set by private insurers and regulated at the state level, so the same Plan K policy can cost $70 a month in one state and $140 in another. A handful of states also use community rating, which charges everyone the same premium regardless of age, changing which plan is cheapest for older versus younger applicants.
Does Medicare Part D affect which Medigap plan is cheapest?
No. Medigap plans do not include prescription drug coverage; you buy a standalone Medicare Part D plan separately regardless of which Medigap letter you choose. Part D has its own $2,100 out-of-pocket cap in 2026 and does not factor into Medigap premium comparisons.
