Medigap

What it means

Medigap policies, also called Medicare supplement insurance, are sold in standardized plan types identified by letters, so the same letter means the same coverage from any insurer.

They work alongside Original Medicare only. Somebody on a Medicare Advantage plan cannot use one.

There is an initial enrollment window during which an insurer must accept an applicant regardless of health. Outside it, in most states, medical underwriting applies.

Why it matters

The enrollment window is the point. Somebody who chooses Medicare Advantage at sixty-five and wants to move to Original Medicare with a Medigap policy at seventy-five may not be able to obtain one.

It also explains why two people with Medicare can face completely different bills for the same treatment.

When you are likely to meet it

• When a parent is choosing Medicare coverage.
• When medical bills arrive despite Medicare coverage.
• When considering a move between Advantage and Original Medicare.

How this varies by state

Whether an insurer may apply medical underwriting outside the initial enrollment window, and what continuous enrollment rights exist, are set by state law.

Related terms

• Creditable coverageDrug coverage at least as good as Medicare's — losing it involuntarily opens a window to enroll.
• Extra HelpA federal subsidy that pays most of the cost of Medicare prescription drug coverage.
• Lifetime reserve daysSixty extra hospital days a person may draw on once in their life, and never get back.
• MedicaidA joint federal and state program that pays for health care, including long-term care, for people with limited income and assets.
• MedicareThe federal health insurance program for people aged sixty-five and over, and for some younger people with disabilities. It does not pay for long-term care.
• Medicare AdvantageMedicare delivered by a private insurance plan instead of directly by the government. It is also called Part C.
• Medicare Part DMedicare's prescription drug coverage, bought as a separate plan from a private insurer.
• Medicare Savings ProgramA state-run program that pays Medicare premiums, and sometimes the deductibles too.
• Skilled nursing facilityA facility providing nursing and rehabilitation care that has to be delivered by licensed clinical staff — not the same thing as a nursing home in the everyday sense.

Official sources

The authority this page describes, at the agency that publishes it. Sahvelo does not restate a rule from a secondary source.

• Medicare — the parts of Medicare (opens in a new tab)

Sahvelo guidance that uses this

• Medicare