There is no official “Medicare Part G.” What most people mean when they search this term is Medigap Plan G, a supplemental insurance policy sold by private companies that covers most of the out-of-pocket costs Original Medicare leaves behind. It’s the most popular and comprehensive Medigap plan available to people who became eligible for Medicare on or after January 1, 2020, and it fills nearly every gap in Medicare Part A and Part B coverage.
Why It’s Called “Plan G,” Not “Part G”
Medicare itself has four parts: Part A (hospital insurance), Part B (medical insurance), Part C (Medicare Advantage), and Part D (prescription drugs). These are federal programs. Medigap plans, on the other hand, are private supplemental policies labeled with letters (A, B, C, D, F, G, K, L, M, and N) that help pay the deductibles, copays, and coinsurance Original Medicare doesn’t cover. Plan G is one of those letter-labeled Medigap options. The confusion between “Part G” and “Plan G” is extremely common, but they refer to the same thing in everyday conversation.
What Plan G Covers
Plan G picks up nearly all the costs that Original Medicare charges you out of pocket. It covers Part A coinsurance and hospital costs for up to an additional 365 days after Medicare benefits run out. It pays your Part B coinsurance and copayments. It covers the first three pints of blood you need in a medical procedure, skilled nursing facility coinsurance, and Part A hospice care coinsurance or copayments.
Two benefits stand out. First, Plan G covers Part B excess charges. These happen when a doctor who accepts Medicare but hasn’t agreed to Medicare’s approved payment amount bills you up to 15% more than what Medicare pays. With Plan G, that extra charge is covered. Second, Plan G includes foreign travel emergency coverage, paying 80% of emergency care costs outside the U.S. after a $250 annual deductible, with a $50,000 lifetime limit. That coverage applies during the first 60 days of any trip.
The one gap in Plan G is the annual Part B deductible, which you pay yourself each year before Medicare Part B starts covering services. In 2025, that deductible is $257. This is the only meaningful out-of-pocket cost Plan G doesn’t eliminate.
How Plan G Compares to Plan F
Plan F used to be the gold standard of Medigap coverage because it covered everything Plan G covers plus the Part B deductible. But a federal law change made Plan F unavailable to anyone who turned 65 on or after January 1, 2020. If you were eligible for Medicare before that date, you can still buy or keep Plan F. Everyone else lands on Plan G as the most comprehensive option available.
The practical difference between the two plans is small. Plan G enrollees pay that annual Part B deductible out of pocket, but Plan G premiums tend to be lower than Plan F premiums, often by enough to more than offset the deductible. Because no new enrollees are entering the Plan F pool, its premiums are expected to rise faster over time as the remaining policyholders age.
What Plan G Costs
Plan G premiums vary significantly by location, age, and insurance company. According to KFF, the average monthly premium among Plan G policyholders in 2023 was $164. That ranged from around $140 in Washington D.C., Hawaii, and New Mexico to $236 in New York. Your actual premium depends on which insurer you choose, your age when you enroll, your zip code, and whether you use tobacco.
There is also a High-Deductible Plan G option for people who want lower monthly premiums in exchange for paying more out of pocket before coverage kicks in. With this version, you pay a $2,870 annual deductible (as of 2025) before the plan begins covering your costs. Monthly premiums for the high-deductible version are substantially lower, sometimes under $50 per month.
What Plan G Does Not Cover
Medigap plans, including Plan G, are designed only to supplement Original Medicare. They do not cover prescription drugs. You need a separate Medicare Part D plan for that. Plan G also excludes dental care, vision care, hearing aids, and long-term care such as nursing home stays or in-home assistance with daily activities. If you need coverage for these services, you would look into standalone dental or vision plans, or in the case of long-term care, a separate long-term care insurance policy.
When and How to Enroll
The best time to buy Plan G is during your Medigap Open Enrollment Period: the six-month window that begins the first day of the month you turn 65 and are enrolled in Medicare Part B. During this window, insurance companies must sell you any Medigap policy they offer at the standard price, regardless of your health history. They cannot charge you more for pre-existing conditions or deny you coverage.
If you miss that window, your options narrow considerably. Outside of open enrollment, insurers in most states can use medical underwriting, which means they can review your health history, charge higher premiums based on existing conditions, or refuse to sell you a policy altogether. A few states have additional protections that extend guaranteed-issue rights, but the federal rule is straightforward: that initial six-month period is your strongest buying opportunity.
One important detail: you cannot pair a Medigap plan with a Medicare Advantage plan. Plan G works only with Original Medicare (Parts A and B). If you’re currently enrolled in Medicare Advantage and want to switch to Original Medicare with a Medigap supplement, you would need to disenroll from your Advantage plan first, and you may face medical underwriting depending on your circumstances and state rules.