TN SB0420

Requires insurers to count cost-sharing amounts paid by enrollees or on their behalf by third parties (such as copay assistance programs) toward deductibles and out-of-pocket maximums

Excludes prescription drugs with generic alternatives from third-party payment counting unless the enrollee obtained brand-name access through prior authorization, step therapy, or appeals processes

Prohibits insurers, pharmacy benefits managers, and third-party administrators from altering health plan coverage terms or benefit design based on the availability of financial or product assistance for prescription drugs

Applies federal annual cost-sharing limits under the Affordable Care Act (42 U.S.C. § 18022) to all healthcare services covered by health plans in Tennessee

Takes effect upon becoming law and applies to health plans entered into, amended, extended, or renewed on or after January 1, 2026