28.1 Purpose of Medigap
Key Takeaways
Medigap supplements Original Medicare by covering deductibles, copays, and coinsurance.
Applicants must be enrolled in Parts A and B to buy a Medigap policy.
The Medigap open enrollment period lasts 6 months after Part B enrollment at age 65+.
Guaranteed issue rights apply in limited situations and require acceptance regardless of health.
Medigap policies do not cover long-term care, and plans sold after 2005 don't include prescription drug coverage.
Standardized benefits ensure comparable coverage across carriers.
Medicare Supplement insurance, commonly called "Medigap," is private insurance that helps pay for costs not covered by Original Medicare (Parts A & B). These policies are designed to fill the "gaps" in Medicare coverage, including deductibles, coinsurance, and copayments.
Why Medigap Exists
Gaps in Original Medicare Coverage
| Gap | Original Medicare Cost | What Medigap Pays |
|---|---|---|
| Part A deductible | $1,736 per benefit period (2026) | Most plans pay 100% |
| Part A coinsurance (days 61-90) | $434/day (2026) | All plans pay 100% |
| Lifetime reserve days | $868/day (2026) | All plans pay 100% |
| Part B deductible | $283/year (2026) | Some plans cover |
| Part B coinsurance | 20% of approved amount | Most plans pay 100% |
| Part B excess charges | Up to 15% above approved | Some plans cover |
The Problem Original Medicare Creates
| Issue | Details |
|---|---|
| No out-of-pocket maximum | 20% coinsurance applies indefinitely |
| Multiple deductibles | Part A (per benefit period) and Part B (annual) |
| No foreign travel coverage | Very limited exceptions |
| Excess charges | Non-participating doctors can charge 15% more |
Key Point: Original Medicare has NO annual out-of-pocket maximum. Someone with a catastrophic illness could face unlimited 20% coinsurance—this is the primary reason people purchase Medigap policies.
How Medigap Works
Basic Structure
| Feature | Details |
|---|---|
| Sold by | Private insurance companies |
| Regulation | Standardized by federal and state law |
| Who can buy | Must have Medicare Parts A and B |
| Premium payment | Monthly premium in addition to Part B premium |
| Covers | Cost-sharing in Original Medicare only |
What Medigap Covers
| Coverage | Description |
|---|---|
| Medicare Part A coinsurance | Hospital costs for days 61-90 and beyond |
| Medicare Part B coinsurance | 20% of doctor visits, outpatient care |
| Blood (first 3 pints) | Part A and Part B blood costs |
| Part A hospice coinsurance | Cost-sharing for hospice care |
| Skilled nursing facility coinsurance | Days 21-100 ($217/day in 2026) |
What Medigap Does NOT Cover
| Not Covered | Alternative |
|---|---|
| Prescription drugs | Medicare Part D |
| Dental care | Separate dental insurance |
| Vision care | Separate vision insurance |
| Hearing aids | Separate coverage needed |
| Long-term care | Long-term care insurance |
| Private-duty nursing | Not covered |
Exam Tip: Medigap plans sold after 2005 don't include prescription drug coverage (some older policies did). Anyone wanting drug coverage with a newer Medigap plan must enroll in a separate Part D plan.
Medigap Open Enrollment Period
The Best Time to Buy
| Feature | Details |
|---|---|
| When it starts | First day of month you're 65+ AND enrolled in Part B |
| Duration | 6 months |
| Protection | Guaranteed issue—cannot be denied for health |
| Pricing | Best available rate—no health surcharges |
| Availability | Can buy ANY Medigap plan sold in your state |
Open Enrollment Rights
| Right | Description |
|---|---|
| No medical underwriting | Health questions don't affect eligibility |
| No denial | Must be sold a policy regardless of health |
| Pre-existing condition waiting period | The insurer may refuse to cover out-of-pocket costs for a pre-existing condition for up to 6 months (6-month look-back), unless you had at least 6 months of continuous creditable coverage |
| Standard pricing | Cannot charge more due to health conditions |
After Open Enrollment Ends
| Situation | What Happens |
|---|---|
| Buying Medigap | Insurers CAN deny coverage based on health |
| Medical underwriting | Must answer health questions |
| Higher premiums | May charge more for health conditions |
| No guarantee | An insurer can refuse to sell a policy if you don't meet its underwriting rules |
Key Point: The 6-month Medigap Open Enrollment Period is a ONE-TIME opportunity. It does NOT repeat each year. Missing this window can make Medigap difficult or impossible to obtain later.
Guaranteed Issue Rights
What Are Guaranteed Issue Rights?
| Feature | Description |
|---|---|
| Definition | Legal right to buy Medigap without underwriting |
| Protection | Cannot be denied or charged more for health |
| When they apply | Specific qualifying situations |
| Time limit | Usually 63 days from loss of coverage |
Situations Creating Guaranteed Issue Rights
| Situation | Plans Available | Time Limit |
|---|---|---|
| Employer group plan that pays after Medicare is ending (including retiree, COBRA or union coverage) | Plan A, B, C*, D*, F* or G* | No more than 63 days after coverage ends |
| Medicare Advantage plan leaves Medicare, stops serving your area, or you move out of its service area | Plan A, B, C*, D*, F* or G* | From 60 days before until 63 days after MA coverage ends |
| Joined MA (or PACE) when first eligible at 65 and leave within the first year (trial right) | Any Medigap policy sold in your state | From 60 days before until 63 days after coverage ends |
| Dropped Medigap to join MA for the first time and leave within the first year (trial right) | The former Medigap policy if the same insurer still sells it; otherwise Plan A, B, C*, D*, F* or G* | From 60 days before until 63 days after coverage ends |
| Medigap insurer goes bankrupt, or coverage ends through no fault of your own | Plan A, B, C*, D*, F* or G* | No more than 63 days after coverage ends |
| Left MA or dropped Medigap because the company broke the rules or misled you | Plan A, B, C*, D*, F* or G* | No more than 63 days after coverage ends |
*Plans C and F are available only to people eligible for Medicare before January 1, 2020; people new to Medicare on or after that date can buy Plan D or G instead. States may add rights.
Medicare Advantage Trial Rights
| Scenario | Right |
|---|---|
| First MA enrollment at 65 | Can leave within the first year and buy any Medigap policy sold in the state |
| Switching from Medigap to MA for the first time | Can return within the first year to the same Medigap policy if the insurer still sells it |
| MA plan leaves Medicare or the area | Guaranteed issue right to Plan A, B, C*, D*, F* or G* |
Exam Tip: Guaranteed issue rights typically last only 63 days from when coverage ends. Applying quickly is essential to avoid coverage gaps.
State Variations
States with Enhanced Protections
| State | Special Rules |
|---|---|
| New York | Continuous open enrollment—can buy anytime |
| Connecticut | Continuous open enrollment—can buy anytime |
| Massachusetts | Different standardized plans |
| Minnesota | Different standardized plans |
| Wisconsin | Different standardized plans |
Additional State Protections
| Protection | States Offering |
|---|---|
| Annual open enrollment | Several states |
| Birthday rule | CA, IL, LA, NV, OR (switch plans without underwriting) |
| Additional guaranteed issue | CA, OR, MO, and others |
Key Point: New York and Connecticut are unique—they allow Medigap enrollment at any time without medical underwriting. Other states only guarantee this during the 6-month open enrollment period.
Key Takeaways
- Medigap supplements Original Medicare by covering deductibles, copays, and coinsurance.
- Applicants must be enrolled in Parts A and B to buy a Medigap policy.
- The Medigap open enrollment period lasts 6 months after Part B enrollment at age 65+.
- Guaranteed issue rights apply in limited situations and require acceptance regardless of health.
- Medigap policies do not cover long-term care, and plans sold after 2005 don't include prescription drug coverage.
- Standardized benefits ensure comparable coverage across carriers.
When does the Medigap Open Enrollment Period begin?
The day you turn 65
The first day of the month you turn 65 and are enrolled in Part B
January 1 of each year
When you retire from your job
How long does the Medigap Open Enrollment Period last?
3 months
6 months
12 months
It repeats annually
Maria enrolled in a Medicare Advantage plan at 65 but is unhappy with the network restrictions. What guaranteed issue right does she have?
None—she must wait until the next Annual Enrollment Period
She can switch to any MA plan immediately
She can leave the MA plan within 12 months and buy a Medigap policy
She must wait 24 months before leaving the MA plan
Which of the following is NOT covered by Medigap plans sold today?
Medicare Part A hospital coinsurance
Medicare Part B coinsurance (20%)
Prescription drugs
Blood (first 3 pints)
Sections you finish are checked off in the contents.