When to buy a Medigap plan

The Medigap open enrollment period

Your Medigap open enrollment lasts 6 months and starts the first day of the month you turn 65 AND are enrolled in Medicare Part B. During this window:

• Insurance companies cannot deny you a policy based on health conditions
• They cannot charge you more because of past or current health problems
• You have guaranteed issue rights to any Medigap plan sold in your state

This is the same time you should be enrolling in a Part D drug plan — the two decisions go hand in hand. Part D enrollment guide →

What happens if you wait?

After your 6-month window closes, insurance companies in most states can:

• Use medical underwriting — ask about your health conditions
• Charge higher premiums based on your health history
• Deny your application entirely

This is very different from Part D, which has an annual open enrollment period. With Medigap, you essentially get one best shot at buying.

Guaranteed issue rights (special situations)

Outside of the open enrollment period, there are specific situations where federal law gives you guaranteed issue rights to buy certain Medigap plans:

• Your Medicare Advantage plan leaves Medicare or stops providing coverage in your area
• You drop a Medigap plan to join a Medicare Advantage plan for the first time, and you want to switch back within 12 months
• Your employer group health plan or Medigap company goes bankrupt or becomes insolvent
• You were misled into dropping your Medigap coverage

Medigap and Part D: enroll in both at the same time

When you're first eligible for Medicare at age 65, you'll typically be making several decisions at once: whether to choose Original Medicare or Medicare Advantage, whether to add a Medigap plan, and which Part D drug plan to select. If you choose Original Medicare, pairing a Medigap plan with a Part D plan gives you the most complete coverage available.

Learn about Part D basics →