Requiring guaranteed issue of medicare supplemental coverage to an individual who voluntarily disenrolls from a medicare advantage plan and enrolls in medicare parts A and B.

HB 1603 requires insurers to offer Medicare supplemental (Medigap) coverage without health-based denial to Washington residents who voluntarily leave a Medicare Advantage plan (Part C) and switch to Original Medicare (Parts A and B). The bill mandates that eligible individuals - specifically those who disenroll from Medicare Advantage and enroll in Parts A/B - must be guaranteed access to a Medigap plan within 63 days of disenrollment, provided they submit proof of termination. This applies to all insurers offering Medigap plans to new enrollees, prohibiting discrimination based on health status or preexisting conditions during this transition window. The policy directly affects seniors switching from Medicare Advantage to Original Medicare, ensuring they can maintain supplemental coverage without barriers. The bill amends Washington’s RCW 48.66.055 to codify this "guaranteed issue" requirement under subsection (3)(b)(E).