Medicare Supplement Plan G pays for costs that Original Medicare leaves you responsible for

Medicare Supplement Plan G is an insurance policy sold by private companies that covers many of the out-of-pocket costs Original Medicare does not. These costs include deductibles, coinsurance, and copayments. Plan G does not replace Original Medicare — you keep your Medicare card and use it the same way. Instead, Plan G works alongside it, stepping in to pay bills after Medicare pays its share.

Plan G is one of ten standardized supplement plans (labeled A through N). The letter determines which costs are covered; Plan G covers more than some plans but not all costs. The monthly premium you pay depends on your age, where you live, and which insurance company sells the plan to you. Different companies charge different prices for the identical coverage, so comparing quotes matters.

You can only buy a supplement plan if you have Original Medicare (Parts A and B). If you have a Medicare Advantage plan instead, supplement plans are not available to you.

Key Takeaways

  • Plan G covers the Part B deductible, coinsurance for hospital and doctor visits, and copayments for skilled nursing facilities, but does not cover the Part A deductible.
  • You pay a monthly premium to the insurance company selling Plan G, separate from your Medicare premium.
  • Plan G is standardized, meaning the coverage is identical no matter which company you buy from — only the price differs.
  • You can switch to Plan G only during specific enrollment periods, or within 63 days of turning 65 and enrolling in Medicare Part B.
  • Plan G does not cover dental, vision, hearing aids, or long-term care — those require separate coverage or out-of-pocket payment.

What Plan G covers and what it does not

Plan G covers the Part B deductible (the amount you pay before Medicare starts paying for doctor visits and outpatient care). It also covers 20% coinsurance for doctor visits, outpatient surgery, and durable medical equipment after you meet the deductible. If you need a blood transfusion, Plan G covers the first three pints. For hospital stays, Plan G covers coinsurance for days 61 through 90 of a hospital stay, and for an additional 60 "lifetime reserve days" if your stay exceeds 90 days.

Plan G also covers copayments for skilled nursing facility care (after Medicare covers the first 20 days). It covers the cost of a second opinion before surgery and covers preventive care copayments.

Plan G does not cover the Part A deductible — the amount you pay for a hospital stay. This is the main difference between Plan G and Plan F (the most comprehensive plan). Plan G also does not cover dental work, vision exams or glasses, hearing aids, or long-term care in a nursing home or at home. These services require separate coverage or payment out of pocket.

How Plan G premiums work and what they cost

You pay Plan G premiums directly to the insurance company, separate from your Medicare premium. The premium is not based on your health — insurance companies cannot deny you or charge you more because of a pre-existing condition, as long as you buy within 63 days of turning 65 and enrolling in Medicare Part B. This protection is called may provide issue.

Premiums vary widely by company and by state. The same Plan G coverage might cost $120 per month with one company and $180 per month with another. Age also affects the premium: some companies charge more as you get older, while others use a "community rate" that does not change with age. Location matters too — premiums in urban areas are often higher than in rural areas.

You should compare quotes from at least three companies before choosing. Many people find quotes through Medicare.gov's Plan Finder tool or by calling companies directly. Once you enroll, you can switch to a different company's Plan G during the annual open enrollment period (October 15 to December 7), though you may face medical underwriting if you switch outside the may provide issue window.

When you can enroll in Plan G

The best time to buy Plan G is within 63 days of turning 65 and enrolling in Medicare Part B. During this window, insurance companies must sell you Plan G at the best rate they offer, regardless of your health history. This is your may provide issue period, and it is the only time you are protected from medical underwriting.

If you miss this window, you can still buy Plan G, but the insurance company can review your medical history and may deny you, charge you more, or exclude certain conditions from coverage. Some states have additional protections that extend may provide issue, so check your state's rules.

You can also switch from one supplement plan to another during the annual open enrollment period (October 15 to December 7 each year). If you switch during this time, you do not need to answer health questions. Outside these windows, switching plans may require medical underwriting.

Plan G versus Plan F and other supplement options

Plan F is more comprehensive than Plan G — it covers the Part A deductible that Plan G does not. However, Plan F is only available to people who were may be able to access for Medicare before January 1, 2020. If you turned 65 on or after that date, Plan F is not an option for you, and Plan G is the most comprehensive supplement plan available.

Plan N is less expensive than Plan G but covers fewer costs. With Plan N, you pay copayments for doctor visits and emergency room visits, and you pay the Part B deductible yourself. Plan N is a good choice if you rarely see doctors and want a lower monthly premium.

Plan A is the least expensive supplement plan but covers very little — mainly hospital coinsurance and some skilled nursing facility costs. Plan A is rarely chosen by people with significant healthcare needs.

Some people choose Medicare Advantage (Part C) instead of Original Medicare plus a supplement. Medicare Advantage plans often have lower premiums but require you to use in-network doctors and may have higher copayments. The choice between Advantage and Original Medicare with a supplement depends on your doctors, your budget, and how much healthcare you use.

How to use Plan G when you see a doctor or go to the hospital

When you see a doctor, you show both your Medicare card and your Plan G card. The doctor's office bills Medicare first. Medicare pays its share, then the bill goes to your Plan G insurance company, which pays the costs Plan G covers. You pay any remaining balance that neither plan covers.

For hospital stays, the process is the same. Medicare pays the hospital, then Plan G pays its share. You are responsible for the Part A deductible (which Plan G does not cover) and any costs beyond what both plans cover together.

You do not need to get prior approval from Plan G for most care — if Medicare covers it, Plan G will cover its portion. However, some procedures may require Medicare approval first. Your doctor's office usually handles this.

Frequently Asked Questions

Can I switch from Plan G to a different supplement plan later?

Yes, you can switch during the annual open enrollment period (October 15 to December 7) without answering health questions. Outside this window, the new company can review your health history and may deny you or charge more. Switching is easiest if you do it during open enrollment.

What happens to my Plan G if I move to a different state?

Your Plan G coverage ends when you move. You must enroll in a new Plan G with a company that operates in your new state. Contact your current insurance company to end your coverage, then compare plans in your new state. You have 63 days to enroll without medical underwriting if you move within that window of turning 65.

Does Plan G cover prescription drugs?

No. Plan G does not cover prescription medications. You need a separate Part D prescription drug plan, which you can enroll in during the annual open enrollment period or when you first turn 65. You can have both Plan G and Part D at the same time.

Will my Plan G premium increase every year?

Yes, most companies raise Plan G premiums annually. The increase varies by company and state. Some people switch to a different company's Plan G during open enrollment if another company offers a lower rate, though you should compare the total cost over time, not just the first year's premium.

What if I have a Medicare Advantage plan — can I switch to Plan G?

You can switch from Medicare Advantage to Original Medicare with Plan G, but only during the annual open enrollment period or if you have a may have access to life event. Once you switch, you cannot go back to Medicare Advantage that same year. Plan the switch carefully with your doctor to make sure your providers accept Original Medicare.