Plan G is a standardized Medicare supplement that covers most of what Original Medicare leaves you to pay

Plan G is one of ten standardized Medicare supplement plans sold by private insurance companies. It covers many of the costs that Original Medicare (Parts A and B) does not — including copayments, coinsurance, and deductibles. Plan G does not cover prescription drugs; you need a separate Part D plan for that.

Plan G is popular because it covers nearly everything Original Medicare leaves unpaid, except the Part B deductible (the amount you pay before Original Medicare starts paying). If you enroll in Plan G, you pay a monthly premium to the insurance company, and then Original Medicare and Plan G split your medical bills according to a fixed formula.

The exact coverage is the same no matter which insurance company sells it to you — that is what "standardized" means. The price and customer service vary by company, but the benefits do not.

Key Takeaways

  • Plan G covers copayments, coinsurance, and most deductibles that Original Medicare does not pay, but you still pay the Part B deductible yourself.
  • You must have Original Medicare Parts A and B to buy Plan G; it works alongside Original Medicare, not instead of it.
  • Plan G does not cover prescription drugs, so you need a separate Part D plan if you take medications.
  • The benefits are identical across all insurance companies, but monthly premiums vary widely — shopping around can save hundreds of dollars per year.
  • You can enroll in Plan G during your Initial Enrollment Period (when you first turn 65) or during the annual Open Enrollment Period (October 15 to December 7).

What Plan G actually covers

Plan G covers the Part A coinsurance — the daily cost you pay for hospital stays after day 60. It covers the Part B coinsurance — the 20% of doctor visits, outpatient surgery, and other services that you normally pay after Original Medicare pays its 80%. It covers blood transfusions (the first three pints per year). It covers skilled nursing facility coinsurance — the daily cost after day 20 in a nursing home.

Plan G also covers Part A hospice coinsurance and foreign travel emergency care (up to 80% of costs, with a $250 deductible and $50,000 lifetime limit). It does not cover the Part B deductible, which is $240 in 2024 — you pay that out of pocket before Original Medicare starts paying anything for doctor visits.

The one major gap in Plan G is prescription drugs. If you take any medications, you must enroll in a Part D plan through Medicare, either when you first sign up for Medicare or during the annual enrollment period. Delaying Part D enrollment can result in a permanent penalty added to your premium.

How Plan G works with Original Medicare

When you see a doctor or go to the hospital, Original Medicare processes the bill first. It pays its share (usually 80% for doctor visits, or a set amount for hospital stays). Then Plan G automatically pays the portion that Original Medicare did not cover, up to the limits of the plan.

You do not file separate claims or switch between insurance companies. The provider bills Original Medicare, Original Medicare sends the bill to your Plan G insurance company, and Plan G pays its share directly. You typically pay nothing at the point of care, or only the Part B deductible if it is your first doctor visit of the year.

This is different from Medicare Advantage (Part C), which replaces Original Medicare entirely. With Plan G, you keep Original Medicare and add a supplement on top.

Plan G premiums and how they are set

Plan G premiums vary by insurance company, your age, your location, and the company's pricing method. Three common methods exist: community-rated (everyone in your area pays the same), age-rated (younger people pay less), and issue-age-rated (your rate is locked based on your age when you enroll).

In 2024, Plan G premiums range from roughly $120 to $300 per month depending on the company and your state, but these numbers change yearly. Some companies increase premiums as you age; others do not. You can switch to a different Plan G from a different company during the annual Open Enrollment Period (October 15 to December 7) without a new medical exam, as long as you have had Plan G for at least 12 months.

The Part B deductible ($240 in 2024) is not part of the Plan G premium — you pay it separately when you see a doctor for the first time each year.

When you can enroll in Plan G

You can enroll in Plan G during your Initial Enrollment Period, which is the six-month window that starts the month you turn 65 or the month you first become may be able to access for Medicare. If you enroll during this period, insurance companies cannot deny you or charge more based on your health history.

If you miss your Initial Enrollment Period, you can enroll during the annual Open Enrollment Period from October 15 to December 7 each year. Coverage begins January 1. Outside these windows, you can only enroll if you have a may have access to life event (such as losing employer coverage) or if you are switching from another Medigap plan.

If you enroll after your Initial Enrollment Period and do not have a may have access to reason, insurance companies may deny you or charge more based on your health. This is called medical underwriting. To avoid this penalty, enroll during your Initial Enrollment Period or during Open Enrollment.

Plan G versus other Medicare supplement plans

Plan G is one of ten standardized plans (A, B, D, G, K, L, M, N, and two high-deductible versions). Plan N is similar to Plan G but costs less because it does not cover the Part B coinsurance for some services and charges a copayment for emergency room visits. Plan F (the most comprehensive) is no longer sold to people new to Medicare as of 2020, though people who had it before that date can keep it.

Plan A is simpler and cheaper but covers less — it does not cover the Part B coinsurance or most deductibles. Plans K and L cover even less and have out-of-pocket limits instead. The right plan depends on how much medical care you expect to use and your budget for premiums.

Plan G is often chosen by people who want broad coverage without worrying about copayments and coinsurance, and who are willing to pay a higher premium for that peace of mind.

What to ask your doctor and insurance company

Before you enroll in Plan G, ask your current doctors whether they accept Original Medicare. Not all providers do, and if your doctor does not accept Medicare, Plan G will not help you see them. You can search for Medicare-accepting providers on Medicare.gov.

Ask your Plan G insurance company whether your medications are covered under Part D (they handle the supplement, not the drugs). Ask whether there are any waiting periods or exclusions for pre-existing conditions — there should not be during your Initial Enrollment Period, but it is worth confirming.

If you are considering switching from one Plan G company to another, ask the new company about the underwriting process and whether they will honor your prior coverage without a new medical exam (they should, if you have had Plan G for at least 12 months).

When to contact Medicare or your insurance company

Contact Medicare (1-800-MEDICARE) if you have questions about your Initial Enrollment Period, whether you have a may have access to life event that lets you enroll outside the annual window, or if you need help understanding how Original Medicare works. Contact your Plan G insurance company if you have questions about your premium, your coverage, or how to file a claim.

If you receive a bill from a provider that you think Plan G should have covered, contact your Plan G insurance company first. If they deny the claim, ask for the reason in writing and consider filing an appeal.

Frequently Asked Questions

Do I have to switch to Plan G if I already have a different Medicare supplement?

No. You can keep your current plan as long as you want. However, if you want to switch to Plan G, you can do so during the annual Open Enrollment Period (October 15 to December 7) without a new medical exam, as long as you have had a Medicare supplement for at least 12 months. Outside this window, the new company may deny you or charge more based on your health.

Will Plan G cover my prescription drugs?

No. Plan G covers only the costs that Original Medicare leaves unpaid. Prescription drugs are covered by Part D, which is a separate plan you buy from a private insurance company. You must enroll in Part D when you first turn 65 or during the annual Open Enrollment Period to avoid a permanent penalty on your premium.

What happens if I turn down Plan G and then change my mind later?

If you miss your Initial Enrollment Period and do not have a may have access to life event, insurance companies can deny you or charge more based on your health history. This is called medical underwriting. You can still enroll during the annual Open Enrollment Period, but the company may charge a higher premium or exclude certain conditions.

Can I use Plan G to see any doctor?

Plan G works with any doctor who accepts Original Medicare. There are no network restrictions like there are with Medicare Advantage. However, some doctors do not accept Medicare at all, and Plan G will not help you see them. You can search for Medicare-accepting doctors on Medicare.gov before you enroll.

How much will Plan G cost me each month?

Plan G premiums vary by insurance company, your age, and your location. In 2024, they typically range from about $120 to $300 per month, but this varies widely. You should get quotes from multiple companies to find the lowest price. Remember that the Part B deductible ($240 in 2024) is separate and not included in the premium.