A retiree shopping for Medigap Plan G in 2026 faces a fork most comparison charts gloss over. The standard version pays nearly every Medicare-covered cost from the first dollar, while a lesser-known high-deductible version leaves the policyholder covering thousands of dollars in coinsurance, copayments and deductibles before the policy pays anything — and insurers price that difference directly into the monthly premium. For a retiree in good health who rarely sees a doctor, the trade can mean a materially smaller bill for coverage that still caps the worst-case exposure. Whether it actually pays off depends on math most shoppers never run before they sign.
Why Plans F and G Both Come in a High-Deductible Version
Medicare Supplement Insurance, known as Medigap, is standardized into a set of lettered plans sold by private insurers to fill the coinsurance, copayment and deductible gaps left by Original Medicare. Two of those letters, Plan F and Plan G, are sold in a second, high-deductible version in states where insurers offer it. The benefits underneath are identical to the standard letter — a high-deductible Plan G eventually covers the same Part A and Part B cost-sharing as a standard Plan G. What changes is the order of who pays first.
Under the terms Medicare publishes for comparing plan benefits, a policyholder in the high-deductible version must pay Medicare-covered coinsurance, copayments and deductibles out of pocket, up to a deductible amount of $2,950 in 2026, before the policy starts paying anything. That figure is set annually and has climbed in recent years, so a shopper comparing quotes needs the current-year number, not one carried over from an old brochure. Once the $2,950 threshold is met for the year, the high-deductible policy behaves exactly like its standard counterpart for the rest of the calendar year.
Not every retiree can shop for the high-deductible version, either. Plan F, in both its standard and high-deductible forms, is closed to anyone who turned 65 on or after January 1, 2020 — for a retiree in that group, Plan G’s high-deductible option is the only version of this trade still on the table. That carve-out matters because the decision isn’t universal: a retiree who aged into Medicare more recently is choosing between a standard Plan G and a high-deductible Plan G, not weighing four different combinations.
Free retirement updates: Miss an enrollment or claim deadline and it may be gone. Our free Retirement Shield newsletter keeps readers ahead of the ones that matter. Get the free newsletter.
How Insurers Price the Same Coverage Differently
Because every insurer selling a given Medigap letter must offer identical benefits, the price is the only real variable a shopper controls. Medicare’s own guidance on comparing Medigap costs lists several factors that move the number on the bill — discounts for non-smokers or automatic payment, whether medical underwriting applies, and whether the insurer offers a high-deductible option, which by design carries a lower premium in exchange for the policyholder’s larger upfront exposure. Two insurers selling the same Plan G letter in the same state can post premiums that differ by hundreds of dollars a month, which is why Medicare advises shoppers to compare the identical letter across multiple companies rather than assume one insurer’s price reflects the market.
The discount is not guaranteed to be dramatic, and Medicare doesn’t publish a national average gap between the standard and high-deductible versions of the same plan letter — insurers set both prices independently, and the spread varies by state and company. What stays consistent is the mechanism: a healthy retiree who expects to file few claims is effectively pre-paying less every month and betting instead that a bad year, if it comes, is affordable to absorb up to the deductible ceiling. That bet gets harder to unwind than it looks, because switching plans later isn’t guaranteed to be underwriting-free.
The high-deductible design isn’t unique to Plans F and G, either — Medicare structures Plans K and L around a similar idea, capping annual out-of-pocket exposure at $8,000 and $4,000 in 2026 rather than covering costs from the first dollar. The mechanism differs in the details, but the underlying trade is the same across all of these lower-premium options: the policyholder accepts a defined ceiling on exposure in exchange for a smaller line item every month, and the specific dollar figures move with Medicare’s annual adjustments rather than staying fixed.
The Enrollment Window That Determines Whether the Trade Holds Up
Medicare guarantees favorable pricing only for a limited window. Federal law gives every new enrollee a six-month Medigap Open Enrollment Period that starts the month they turn 65 and are enrolled in Part B; during that window, an insurer can’t refuse to sell a policy or charge more because of a pre-existing condition. A retiree who wants to test the high-deductible version, or switch into it later after starting with a standard plan, may not get that same protection — outside the open enrollment window, insurers are generally allowed to use medical underwriting and can deny an application altogether.
That asymmetry cuts against casually switching plan types once the initial window closes. Medigap policies are guaranteed renewable — under Medicare’s rules, an insurer can drop a policyholder only for nonpayment, application fraud or its own insolvency, not for a change in health. That protection covers keeping the policy already in force; it doesn’t extend to buying a new one. A healthy 65-year-old who locks in a high-deductible Plan G during the open enrollment window keeps that pricing and protection for as long as premiums are paid, but a retiree who develops a chronic condition and later wants to trade the higher deductible for first-dollar coverage may face medical underwriting on the way out.
That timing detail is the practical crux of the decision. The premium savings from a high-deductible Plan F or Plan G are real and compound every month a healthy retiree pays less than a neighbor with the standard version, but the policy is only as good as the retiree’s ability to cover up to $2,950 in a single bad year without missing a housing or grocery payment. Retirees weighing the switch have the strongest hand during their one-time enrollment window — waiting to decide until after a health scare removes the leverage that made the high-deductible option worth considering in the first place.
This article was produced with the assistance of AI and reviewed by The Money Overview editorial team before publication.
More Financial Reading
