3.2 Washington Medicare Supplement (Medigap) Regulations

Key Takeaways

  • Medigap open enrollment is a one-time 6-month window starting the month you are 65+ AND enrolled in Part B; underwriting is barred during it.
  • Washington goes far beyond the federal floor: residents may switch Medigap plans year-round with no health underwriting (continuous guaranteed issue).
  • Federal guaranteed-issue triggers give a 63-day window when losing group coverage, leaving Medicare Advantage, or an insurer becoming insolvent.
  • Medigap plans are standardized A through N; Plans C and F (which pay the Part B deductible) are closed to anyone first Medicare-eligible on/after Jan 1, 2020.
  • SHIBA volunteers provide free counseling and the OIC reviews and approves all Medigap rate filings under RCW 48.
Last updated: June 2026

Medicare Supplement Basics

Medicare Supplement (Medigap) is private insurance that pays the gaps in Original Medicare - deductibles, coinsurance, and copays. It is sold by letter-plan (A through N) and is standardized: every Plan G sold by any carrier has identical benefits, so beneficiaries shop on price and service, not benefit design. Medigap pairs only with Original Medicare (Parts A and B); it does not work with a Medicare Advantage (Part C) plan, and selling Medigap to someone on Advantage who is not disenrolling is an illegal practice.

Open Enrollment Period (6 Months, One Time)

The Medigap Open Enrollment Period (OEP) is a one-time 6-month window that starts on the first day of the month in which the individual is both age 65 or older AND enrolled in Medicare Part B. During OEP:

  • Guaranteed issue - the carrier must accept the applicant regardless of health.
  • No pre-existing condition waiting periods can be imposed (Washington bars them).
  • No health-based rate-up - the applicant pays the standard rate for any plan A-N.
ItemRule
Duration6 months
TriggerAge 65 + enrolled in Part B
UnderwritingProhibited
Plan choiceAny plan A-N the carrier offers

Exam tip: OEP is one-time and tied to Part B start. A 67-year-old who delayed Part B because of active employer coverage gets a fresh 6-month OEP when Part B finally begins - not a missed deadline.

Washington's Year-Round Guaranteed Issue (KEY DIFFERENCE)

This is the single most-tested Washington Medigap fact. Unlike most states - and unlike the limited "birthday rule" states such as California or Oregon - Washington lets beneficiaries change Medigap plans at ANY time of year with NO health underwriting. The rule:

  • A beneficiary on Plan A may switch to another Plan A without underwriting.
  • A beneficiary on any plan other than A may switch to any other plan (more or less coverage) without underwriting.

So a Washington enrollee is never locked into a plan by their health. The trap answer says Washington only allows changes during a 30-day birthday window - that describes Oregon/California, not Washington's broader continuous guaranteed issue.

Federal Guaranteed-Issue Triggers (63-Day Windows)

Independent of Washington's year-round rule, federal law grants guaranteed-issue rights after certain events, generally exercisable within 63 days of losing coverage:

Triggering eventRight granted
Losing employer/union group health coverageBuy Medigap within 63 days
Medicare Advantage plan leaves your area or you move out of its service areaBuy Medigap
Medigap or Advantage insurer becomes insolvent / commits misrepresentationSwitch to a comparable plan
You drop Medigap to try Medicare Advantage for the first time and switch back within 12 months (trial right)Return to your prior Medigap (or any plan from that insurer)
Losing Medicaid eligibilityBuy Medigap

The trial right ("first-time MA, 12-month look-back") is heavily tested: a beneficiary who tries Medicare Advantage for the first time may return to their old Medigap, guaranteed issue, if they disenroll within 12 months.

Standardized Plans A-N

PlanNotable feature
ACore/basic benefits only
BCore + Part A deductible
CComprehensive incl. Part B deductible - closed to new enrollees
DLike C without the Part B deductible
FMost comprehensive, pays Part B deductible - closed to new enrollees (high-deductible F also closed)
GLike F but no Part B deductible - top seller for new enrollees
K50% cost-sharing with out-of-pocket maximum
L75% cost-sharing with out-of-pocket maximum
M50% of Part A deductible
NLower premium; copays up to $20 office / $50 ER

Plans C and F pay the Part B deductible, which federal law (MACRA) barred new plans from covering. So anyone first eligible for Medicare on or after January 1, 2020 cannot buy C or F; they typically pick Plan G instead. Someone eligible before 2020 keeps access to C and F.

Rating and Consumer Help

Washington carriers may use attained-age, issue-age, or community rating, and every rate increase must be filed with and reviewed by the OIC under RCW 48. Free, unbiased counseling comes from SHIBA - Statewide Health Insurance Benefits Advisors, a volunteer program run by the OIC. A producer cannot charge a fee for SHIBA-type counseling and should refer confused beneficiaries to it.

Exam tip: "Standardized but priced differently" is the recurring Medigap theme - benefits are identical by letter, so the differences a producer explains are price, rating method, and the carrier's rate-increase history.

Marketing and Replacement Rules

Washington and the NAIC model regulation tightly control how Medigap is sold:

  • Suitability: a producer may not sell a beneficiary a duplicate Medigap policy or one that does not improve coverage; selling a second Medigap when one already exists is prohibited.
  • Replacement notice: when a sale replaces existing Medigap or other health coverage, the producer must deliver a replacement notice and document why the change benefits the client.
  • Outline of coverage must be delivered at the time of application.
  • Cooling-off / free look: Medigap policies carry a 30-day free look in Washington - longer than the 10-day health free look.
  • High-pressure tactics, cold-lead misrepresentation, and using deceptive Medicare-branded mailers are unfair trade practices subject to OIC fines and license action.

Worked scenario: A client already owns Plan G. A producer who sells her a second Plan F "for extra protection" has violated anti-duplication rules - the policies overlap and the second pays nothing Medicare or Plan G has already covered, exposing the producer to discipline.

Test Your Knowledge

What makes Washington's Medicare Supplement switching rules more generous than typical states?

A
B
C
D
Test Your Knowledge

When does the one-time 6-month Medicare Supplement open enrollment period begin?

A
B
C
D
Test Your Knowledge

Which Medicare Supplement plans are closed to people first eligible for Medicare on or after January 1, 2020?

A
B
C
D