This bill adds a new section to chapter 48.43 RCW that requires nongrandfathered group health plans (except small group plans and public employee plans under chapter 41.05 RCW) issued or renewed on or after January 1, 2026, to cover prosthetic limbs and custom orthotic braces per limb when medically necessary to enable specified activities. Coverage must include the device materials and components, related services, instruction in device use, and reasonable repair or replacement. Replacement or repair must be covered regardless of continuous use or useful lifetime limits when medically necessary because of a physiological change, an irreparable device change, or when repair would cost more than 60% of replacement; plans may require confirmation from the prescribing provider for replacements less than three years old. The bill also prohibits denying coverage to an enrollee with a disability if the same services would be covered for a nondisabled person seeking similar medical or surgical intervention to restore or maintain the same physical activity. Plans may continue to apply normal utilization management and prior authorization practices, but any denial must be written and explain why the care was not medically necessary. Carriers must provide payment and coverage at least equal to specified federal Medicare-related statutes and regulations (42 U.S.C. §§1395k, 1395l, 1395m; 42 C.F.R. §§414.202, 414.210, 414.228, 410.100). The bill creates new benefit and reporting requirements and adds definitions for "prosthetic limb" and "custom orthotic brace." Carriers must report the number and total paid amount of claims for plan years 2026 and 2027 to the insurance commissioner by July 1, 2028; the commissioner must aggregate the data by plan year and report to relevant legislative committees by December 1, 2028. The text provided does not define "medically necessary" or "nongrandfathered," does not specify which legislative committees will receive the report, and does not describe the form and manner of reporting or any enforcement mechanisms or penalties.

If enacted, most nongrandfathered employer group health plans in Washington (except small group plans and public employee plans under chapter 41.05 RCW) must cover prosthetic limbs and custom-fitted orthotic braces when medically necessary, including the devices, parts, related services, training, and reasonable repair or replacement under specified conditions. Coverage must also meet certain Medicare-based payment and coverage standards, plans can still use prior authorization and utilization management, and replacements under three years may require confirmation from the prescribing provider; the rule applies to plans issued or renewed on or after January 1, 2026. The direct impacts will fall mainly on insurers and employers who sponsor affected plans, who are likely to see higher claims costs and added administrative tasks (including mandatory claims reporting for 2026–2027 to the insurance commissioner by July 1, 2028, and an aggregated legislative report by December 1, 2028), which could translate into higher premiums or stricter utilization controls. Providers may face more documentation requests for replacements less than three years old. Key implementation details remain unclear here, including exact definitions of "medically necessary" and "nongrandfathered," the reporting format the commissioner will require, and enforcement mechanisms, so those uncertainties could affect how quickly and uniformly plans change.