Something significant shifted in the Medicare Advantage market heading into 2026. After years of aggressive expansion — flashy dental, vision, and gym benefits used to recruit millions of seniors — Medicare Advantage insurers began pulling back. Major carriers reduced or eliminated supplemental benefits, narrowed provider networks, and in many markets raised the out-of-pocket maximums that beneficiaries could face in a bad health year. For retirees who enrolled in Medicare Advantage expecting low costs and rich extras, the 2026 plan year has been a wake-up call. And it has sent many of them looking seriously at Medigap Plan G for the first time.
Medigap Plan G is a standardized Medicare supplement insurance policy sold by private insurers but regulated by the federal government. Because it's standardized, the benefits are identical regardless of which insurance company sells it — the only difference between carriers is the monthly premium. In 2026, Plan G covers 100% of Medicare Part A coinsurance and hospital costs, Part A hospice care coinsurance, skilled nursing facility coinsurance, Part B coinsurance and copayments, and the Part A deductible, which is $1,676 per benefit period in 2026. The only cost Plan G does not cover is the Medicare Part B annual deductible, which is $257 in 2026. Once you've paid that $257 out of pocket, Plan G essentially covers the rest of your Medicare-approved medical expenses for the year. That's a fundamentally different financial structure than Medicare Advantage.
The first and most compelling reason to choose Plan G over Medicare Advantage in 2026 is cost predictability. With Medicare Advantage, your actual annual costs depend heavily on how much care you use and whether your providers are in-network. In-network out-of-pocket maximums for Medicare Advantage plans can legally reach $9,350 in 2026, and combined in- and out-of-network maximums can go even higher. If you have a serious illness, a surgery, or a prolonged hospital stay, you could be responsible for thousands of dollars in cost-sharing before hitting that cap. With Plan G, your maximum predictable out-of-pocket exposure for covered services is essentially that $257 Part B deductible. Monthly premiums for Plan G vary by age, location, and insurer — typically ranging from roughly $100 to $200 per month for a 65-year-old, and higher for older enrollees — but that premium buys you near-total elimination of medical cost surprises.
The second reason is provider access. Medigap Plan G works with any doctor, specialist, or hospital in the United States that accepts Medicare — and roughly 93% of non-pediatric physicians do. There are no networks, no referrals required to see a specialist, and no prior authorization from a private insurance company standing between you and your physician's recommended treatment. Medicare Advantage plans, by contrast, use provider networks — HMO plans typically require you to stay in-network except for emergencies, while PPO plans allow out-of-network care but at significantly higher cost-sharing. If your preferred cardiologist, oncologist, or orthopedic surgeon isn't in your Medicare Advantage plan's network — or drops out mid-year — you either pay more or find someone new. For retirees who travel frequently, split time between two states, or simply want to see the best specialist available, Plan G's nationwide unrestricted access is a major practical advantage.
The third reason involves what's happened to Medicare Advantage's supplemental benefits. For several years, the extra perks — dental coverage, vision allowances, hearing aid benefits, over-the-counter product credits, transportation, and fitness memberships — were a primary selling point for Medicare Advantage. In 2026, many of those benefits have been scaled back significantly. CMS tightened the rules around what counts as a permissible supplemental benefit, and insurers facing margin pressure responded by cutting or capping extras that were previously generous. A dental benefit that once covered $2,000 in services may now cover only cleanings and X-rays. An over-the-counter allowance that was $100 per quarter may have dropped to $50 or been eliminated entirely. Retirees who chose Medicare Advantage specifically for those extras and are now seeing them disappear are paying Advantage premiums — sometimes $0, sometimes $50 to $100 per month — without the value proposition that justified the tradeoff.
The fourth reason is the prior authorization problem. Medicare Advantage plans are legally permitted to require prior authorization before approving certain treatments, procedures, imaging studies, and post-acute care like skilled nursing or home health. CMS has taken steps to tighten prior authorization rules, including a 2024 regulation requiring faster decisions and more transparency, but prior authorization remains a structural feature of Medicare Advantage that does not exist in Original Medicare with a Medigap supplement. When you have Plan G and Original Medicare, your doctor orders a test or procedure, Medicare determines whether it's covered, and it gets done. There's no insurance company reviewing whether your MRI is medically necessary or whether your 10-day skilled nursing stay should be cut to 7. For retirees managing complex or chronic conditions, that difference in administrative friction is not trivial — it can affect the timeliness and completeness of care.
The fifth reason is long-term financial planning. Medicare Advantage plans change every single year. Benefits, premiums, copayments, networks, and formularies can all shift at annual renewal. A plan that worked well for you in 2025 may have a different structure in 2026, and you have to actively review it during the Annual Enrollment Period — October 15 through December 7 — to catch those changes. If you don't review and your plan deteriorates, you may be stuck with it for the year. Medigap Plan G, by contrast, is stable. The benefit structure is set by federal standardization. Your premium may increase modestly over time, but the coverage itself doesn't change. For retirees who want to set their healthcare financial plan and not revisit it every fall, that stability has real value. It also matters for estate planning and budgeting — knowing your maximum healthcare exposure for the year allows for more precise financial planning.
There is one important caveat that every retiree considering this switch needs to understand: Medigap medical underwriting. If you are already enrolled in Medicare Advantage and want to switch to Medigap Plan G, you generally must pass medical underwriting in most states — meaning the insurer can review your health history and either charge you more, exclude pre-existing conditions, or deny coverage entirely. The guaranteed issue rights that allow you to buy Medigap without underwriting apply in specific situations: when you first become eligible for Medicare Part B at 65, when you lose employer coverage, or when your Medicare Advantage plan leaves your area or you move out of its service area. Outside of those windows, underwriting applies in most states.
A meaningful exception exists in states that have enacted birthday rule protections. In California, Idaho, Illinois, Kentucky, Louisiana, Maine, Maryland, Missouri, Nevada, New Jersey, New York, Oklahoma, and Oregon, beneficiaries have a window — typically 30 days around their birthday — to switch from one Medigap plan to another of equal or lesser benefit without medical underwriting. Some of these states extend that right to switching from Medicare Advantage to Medigap as well, though the specific rules vary. If you live in one of these states, your birthday window may be your opportunity to make this switch without health screening. Contact your state's insurance department to confirm the exact rules in your state before acting.
For retirees who are newly turning 65 or newly enrolling in Medicare Part B, the calculus is clearer. You have a six-month Medigap open enrollment window starting the month your Part B begins, during which any insurer offering Medigap in your state must sell you any plan they offer at standard rates, regardless of your health history. This is the single best opportunity to lock in Plan G coverage, and it cannot be repeated. Missing this window and choosing Medicare Advantage instead means that switching to Medigap later will likely require passing underwriting — a significant barrier for anyone with diabetes, heart disease, cancer history, or other common conditions.
When comparing costs, it's worth doing the actual math for your situation. If Plan G premiums run $150 per month in your area, that's $1,800 per year plus the $257 Part B deductible — roughly $2,057 in known costs for covered services. A Medicare Advantage plan with a $0 premium but a $9,350 out-of-pocket maximum represents a potential $9,350 exposure in a serious health year. For a retiree in good health who uses minimal care, Advantage may cost less in a given year. But for anyone managing ongoing conditions, taking regular specialist visits, or facing the statistical reality that healthcare use increases with age, Plan G's ceiling on costs may represent better value over a multi-year horizon. The break-even point shifts considerably once you factor in a hospitalization, a cancer diagnosis, or a joint replacement.
To find Plan G premiums in your specific ZIP code, Medicare.gov's plan finder tool allows you to compare Medigap premiums from all insurers licensed in your area. Premiums for the same Plan G can vary by 50% or more between insurers for the same beneficiary, so comparison shopping is essential. The State Health Insurance Assistance Program, known as SHIP, offers free one-on-one counseling in every state to help you evaluate your options without any sales pressure. You can reach SHIP through Medicare.gov or by calling 1-800-MEDICARE.