Financial Basics · Healthcare

Medigap

Definition

Medigap (Medicare Supplement) is private insurance that covers the 20% coinsurance and other out-of-pocket costs Original Medicare doesn't pay. Plans are standardized by letter (A through N) with Plan G being the most comprehensive available to new enrollees.

Why it matters in retirement

Paired with Original Medicare and a Part D plan, a Medigap policy gives you nearly unlimited medical coverage with almost no out-of-pocket cost and no network restrictions. For many retirees this is the gold standard — if you enroll during your open enrollment window.

Key Numbers — 2026

Avg Plan G premium (65)
$150–$250/mo
Plan G deductible
$257 (Part B)
Open enrollment window
6 months from Part B
Part B coinsurance
20% (uncapped)

Pros

  • No network restrictions
  • No prior auth
  • Predictable costs
  • Guaranteed renewable

Cons

  • Higher monthly premium than Advantage
  • No dental/vision/hearing
  • Premiums rise with age (attained-age plans)
  • Must apply during open enrollment or face underwriting

Common mistakes

  • Missing the 6-month open enrollment window
  • Buying Plan F (no longer available to new enrollees after 2020)
  • Not comparing Plan G vs Plan N (Plan N often saves money)
  • Ignoring "community-rated" vs "attained-age" pricing

Related

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