Medicare Supplement Plan G: What It Covers and What It Costs

Medicare Supplement Plan G has quietly become the dominant Medigap policy sold in the United States, and for good reason. As Original Medicare's cost-sharing gaps have grown — Part A hospital deductibles hit $1,676 per benefit period in 2025, and Part B still leaves you responsible for 20% of most outpatient costs with no annual cap — Plan G fills nearly every one of those holes. Understanding exactly what it covers, what it costs, and how it compares to the alternatives can mean the difference between a policy that genuinely protects your finances and one that leaves you exposed.

Plan G is one of ten standardized Medigap plans sold by private insurers and regulated by the Centers for Medicare & Medicaid Services (CMS). Because the federal government standardizes the benefits, every insurer selling Plan G in your state must offer the exact same coverage — no more, no less. What differs between companies is the premium you pay each month. That standardization is enormously important: it means you can compare plans from Aetna, Mutual of Omaha, UnitedHealthcare, and dozens of regional carriers purely on price, without worrying that one company's Plan G is somehow better than another's.

Here is what Plan G actually covers in 2025. It pays the Part A hospital deductible ($1,676 per benefit period), Part A coinsurance and hospital costs for up to 365 days after your Medicare benefits are exhausted, Part A hospice care coinsurance or copayments, Part B coinsurance or copayments (that critical 20% of outpatient costs), the first three pints of blood each year, skilled nursing facility care coinsurance, and 80% of emergency medical costs during foreign travel (up to a $50,000 lifetime limit, after a $250 deductible). The only gap Plan G does not fill is the Medicare Part B deductible, which is $257 in 2025. Once you pay that deductible each calendar year, Plan G covers the rest. For most beneficiaries who see doctors regularly, that $257 is the entirety of their predictable annual out-of-pocket exposure for Medicare-covered services.

The comparison most beneficiaries face is between Plan G and its two closest competitors: Plan F and Plan N. Plan F is the only Medigap policy that also covers the Part B deductible, making it truly comprehensive with zero out-of-pocket costs for covered services. However, Congress closed Plan F to new enrollees beginning January 1, 2020, as part of the Medicare Access and CHIP Reauthorization Act (MACRA). If you became eligible for Medicare on or after that date, Plan F is simply not available to you — Plan G is the most comprehensive option you can legally purchase. Beneficiaries who were Medicare-eligible before January 1, 2020 may still purchase or keep Plan F, but premiums tend to run $30 to $60 per month higher than Plan G, and since the only additional benefit is that $257 deductible, the math rarely favors Plan F for new purchasers.

Plan N is the other major alternative worth understanding. Plan N covers the same broad list as Plan G with two important differences: you may owe up to a $20 copayment for office visits and up to a $50 copayment for emergency room visits that don't result in inpatient admission, and Plan N does not cover Part B excess charges. Excess charges occur when a doctor does not accept Medicare assignment and bills up to 15% above the Medicare-approved amount. In states that prohibit excess charges — including Ohio, Massachusetts, Connecticut, Minnesota, New York, Pennsylvania, and Rhode Island — Plan N's gap is less significant. In states where excess charges are common, Plan G's broader protection has real value. Plan N premiums typically run $20 to $60 per month less than Plan G, so if you rarely visit specialists and live in a state that limits excess charges, Plan N may offer better value. But if you have ongoing specialist care or want the simplicity of knowing your costs are capped at $257 per year, Plan G's predictability is worth the premium difference for many beneficiaries.

Premium pricing for Plan G is where beneficiaries need to do serious homework. Insurers use three different methods to set premiums. Community-rated plans charge everyone the same premium regardless of age — these tend to be more affordable for older enrollees. Issue-age-rated plans base your premium on the age you were when you first bought the policy and don't increase it as you age, though they do adjust for inflation. Attained-age-rated plans — the most common type — start lower but increase as you get older, which can make them significantly more expensive in your 70s and 80s. A 65-year-old in good health might find Plan G premiums ranging from $100 to $180 per month in many markets, while a 75-year-old shopping for the same coverage could face premiums of $180 to $300 or more depending on location and insurer. Your state's insurance commissioner website is the best place to compare actual premium quotes from all licensed insurers in your area — most state departments of insurance maintain online comparison tools specifically for Medigap.

The best time to buy Plan G — or any Medigap policy — is during your Medigap Open Enrollment Period, which begins the month you turn 65 and are enrolled in Medicare Part B, and lasts for six months. During this window, insurers cannot deny you coverage or charge you higher premiums based on pre-existing health conditions. This is your strongest consumer protection, and it does not repeat. After this window closes, insurers in most states can use medical underwriting, meaning a history of heart disease, diabetes, cancer, or other conditions can result in higher premiums or outright denial. There are limited Special Enrollment Periods — for example, if you lose employer coverage or your Medicare Advantage plan leaves your area — but these are narrower than the initial open enrollment window.

A handful of states offer additional protections worth knowing. California, Idaho, Illinois, Kentucky, Louisiana, Maine, Maryland, Missouri, Nevada, New Jersey, New York, Oklahoma, and Oregon have birthday rules that give Medigap enrollees a 30-day window each year around their birthday to switch to a plan with equal or lesser benefits without medical underwriting. New York and Connecticut offer guaranteed issue rights year-round, meaning insurers cannot deny Medigap coverage regardless of health status. If you live in one of these states, your ability to shop for better premiums later in life is meaningfully stronger than in states without these protections.

One cost-saving strategy worth exploring is the High-Deductible Plan G, which became available in 2020. This version carries the same benefits as standard Plan G but requires you to pay a deductible — $2,870 in 2025 — before the plan begins covering costs. In exchange, monthly premiums can be dramatically lower, sometimes $40 to $80 per month compared to $130 to $180 for standard Plan G. For beneficiaries who are generally healthy and want catastrophic protection without high monthly premiums, High-Deductible Plan G functions somewhat like a high-deductible health plan in the commercial market. The break-even calculation depends on your health usage, but for someone who rarely hits the standard Plan G's $257 annual exposure, the lower premiums of the high-deductible version may produce meaningful savings over time.

Finally, it is worth understanding what Plan G does not cover, because no Medigap policy covers everything. Plan G does not cover Medicare Part D prescription drug costs — you will need a separate Part D plan for that. It does not cover dental, vision, or hearing care, which Original Medicare also excludes. It does not cover long-term custodial care in a nursing home. And it does not work alongside Medicare Advantage — Medigap policies are only compatible with Original Medicare (Parts A and B). If you are currently enrolled in a Medicare Advantage plan and want to switch to Original Medicare plus Plan G, you can do so during the Annual Enrollment Period (October 15 through December 7) or the Medicare Advantage Open Enrollment Period (January 1 through March 31), but be aware that switching back to Medigap after a period on Medicare Advantage may trigger medical underwriting in most states.