MS HB558

Prohibits health insurers and pharmacy benefit managers (PBMs) from requiring patients to obtain prescriptions exclusively through pharmacies they own, including regular and specialty drugs regardless of day supply

Bars insurers and PBMs from implementing plan designs that impose higher premiums, deductibles, copayments, or coinsurance on patients who choose not to use insurer-owned or PBM-owned pharmacies

Requires insurers and PBMs to reimburse independent pharmacies at rates equal to what they pay pharmacies in which they have ownership interest for the same services

Mandates that any pharmacy willing to accept established network terms and conditions must be allowed to participate in pharmacy networks at preferred status

Effective date: July 1, 2026