Creates provisions relating insurance coverage of medically necessary health care services

HB 871 requires Missouri insurance companies and state health programs (like MO HealthNet and Medicaid managed care) to cover medically necessary health care services. Specifically, these insurers cannot deny coverage for a service if two health care professionals determine it is medically necessary to diagnose, treat, prevent, or relieve a health condition. The law applies to all health benefit plans sold or renewed in Missouri after January 1, 2026. It does not specify which services qualify as "medically necessary" but mandates this two-professional review process for coverage decisions. The bill affects all private insurers and state-sponsored health plans offering coverage for health care services in Missouri.