13.2 Medicare Supplement (Medigap) Policies
Key Takeaways
- Medigap is private insurance that fills 'gaps' (deductibles, coinsurance) in Original Medicare; it does NOT work with Medicare Advantage.
- Plans are standardized into lettered types (A, B, C, D, F, G, K, L, M, N) so that Plan G from any insurer offers identical benefits — insurers compete only on price and service.
- The 6-month Medigap Open Enrollment Period begins the month a person is 65+ AND enrolled in Part B, guaranteeing issue with no medical underwriting.
- Plans C and F (which cover the Part B deductible) are closed to anyone newly eligible for Medicare on or after January 1, 2020.
- Every Medigap policy carries a 30-day free-look period and is guaranteed renewable for life as long as premiums are paid.
A Medicare Supplement (Medigap) policy is private insurance designed to pay the cost-sharing amounts Original Medicare does not — chiefly the Part A deductible, the Part B 20% coinsurance, and various copays. Because Part B has no out-of-pocket cap, Medigap is how seniors limit catastrophic exposure while keeping Original Medicare's nationwide provider freedom.
Standardization — The Heart of the Topic
Federal law (OBRA 1990) requires Medigap plans to be standardized into lettered packages. A given letter offers identical benefits at every company, so Plan G from Insurer X equals Plan G from Insurer Y. Insurers compete only on price, service, and stability.
| Plan | Notable Feature |
|---|---|
| A | Basic benefits only (the floor every insurer must offer) |
| B | Adds Part A deductible |
| C | Covers Part B deductible — closed to new enrollees after 1/1/2020 |
| F | Most comprehensive; covers Part B deductible — closed after 1/1/2020 |
| G | Like F but NOT the Part B deductible — now the top seller |
| K, L | Cost-sharing plans (50%/75%) with out-of-pocket limits |
| M, N | Cost-sharing variants; N uses office/ER copays |
Exam Trap: Plans C and F are closed to anyone first eligible for Medicare on or after January 1, 2020, because they covered the Part B deductible. Already-enrolled beneficiaries keep them.
Core Rules Every Candidate Must Know
| Rule | Standard |
|---|---|
| Free-look period | 30 days |
| Renewability | Guaranteed renewable for life if premiums paid |
| Works with | Original Medicare only — NOT Medicare Advantage |
| Drug coverage | None — Medigap does NOT include Part D |
| One policy | Illegal to sell a 2nd Medigap to someone who already has one |
Key Point: It is illegal for an agent to sell a Medigap policy to someone enrolled in a Medicare Advantage (Part C) plan, because the supplement would duplicate coverage. This is a frequently tested unfair-trade-practice scenario.
Medigap Open Enrollment — Guaranteed Issue
The single most important timing rule: the Medigap Open Enrollment Period is a one-time 6-month window that begins the first month a person is both age 65 or older AND enrolled in Part B. During this window the applicant has guaranteed issue — the insurer cannot deny coverage, charge more, or impose a longer pre-existing waiting period because of health.
| Inside 6-Month OEP | Outside the Window |
|---|---|
| Guaranteed issue — no underwriting | Insurer may medically underwrite |
| Cannot be turned down for health | Can be declined or rated up |
| Pre-existing limit capped (max 6 months) | Coverage not guaranteed |
Worked Scenario: A woman turns 65 in March but delays Part B until she retires in September. Her 6-month Medigap OEP runs September–February (it starts when Part B begins, not at age 65). Counsel clients to align Part B and Medigap timing.
Pre-Existing Conditions
During open enrollment, an insurer may impose at most a 6-month waiting period for conditions treated within the prior 6 months — but if the applicant had 6 months of prior creditable coverage, even that waiting period is waived.
Replacement
When replacing one Medigap with another, the agent must deliver a replacement notice and the applicant must sign a statement of intent to replace. The new policy may not re-impose a pre-existing waiting period already satisfied under the old policy. Churning policies for commission is an unfair practice.
Why Standardization Matters on the Exam
Because every insurer's Plan G is identical to every other insurer's Plan G, a candidate is expected to know that comparison shopping is purely about price and service, never benefits. This is a favorite test point: if a question asks how two Plan N policies differ, the answer is premium and the company's reputation, not coverage.
| Concept | Tested Fact |
|---|---|
| Standardized letters | A, B, D, G, K, L, M, N (C & F closed after 1/1/2020) |
| Free-look | 30 days |
| Open enrollment | One-time 6 months at 65 + Part B |
| Pairs with | Original Medicare only, never Advantage |
| Drug coverage | None — buy Part D separately |
Guaranteed Issue Beyond Open Enrollment
Certain guaranteed-issue rights arise outside the 6-month window — for example, when an employer plan ends, a Medicare Advantage plan leaves the area, or a "trial right" allows a return to Medigap within 12 months of first joining Advantage. These let beneficiaries buy specified Medigap plans without underwriting.
Worked Example: A man drops his Medicare Advantage plan within his first 12 months and returns to Original Medicare. His trial-right guaranteed issue lets him buy a Medigap plan with no health questions, even though his one-time 6-month OEP has passed.
Exam Trap: Selling a Medigap policy to someone enrolled in Medicare Advantage is an illegal duplication; and an agent may not sell a second Medigap to a person who already has one. Both are unfair trade practices tested repeatedly.
Pre-Existing Conditions and Creditable Coverage
Even inside the 6-month open enrollment window an insurer may apply a pre-existing-condition waiting period of up to 6 months for conditions treated in the prior 6 months — but prior creditable coverage offsets that waiting period day-for-day, often eliminating it entirely for someone moving from an employer plan.
Exam Tip: Pair the 30-day free look, the 6-month open enrollment, and the 6-month maximum pre-existing wait together — the exam frequently tests all three numbers in one Medigap question.
Because Medicare Supplement plans are standardized, which statement is TRUE?
A man turns 65 in April but keeps working and does not enroll in Part B until he retires the following January. When does his 6-month Medigap Open Enrollment Period begin?