Insurance, Health, Accident - As introduced, prohibits an insurer, pharmacy benefits manager, or third-party administrator from changing or conditioning the terms of health plan coverage based on availability of financial or other product assistance for a prescription drug; establishes certain procedures for calculating an enrollee's contribution to an applicable cost sharing requirement. - Amends TCA Title 4; Title 8; Title 10; Title 53; Title 56; Title 63; Title 68 and Title 71.

HB 870 prohibits insurers, pharmacy benefits managers, and third-party administrators from altering health plan coverage terms based on whether a patient qualifies for financial or product assistance for prescription drugs. The bill requires insurers to calculate enrollees' out-of-pocket costs using standard methods, including amounts paid by others on the enrollee's behalf, and explicitly bans conditioning coverage on drug assistance availability. It directly affects health plan enrollees and the entities managing prescription drug benefits in Tennessee. The law applies to health plans entered into, amended, or renewed on or after January 1, 2026, and amends multiple sections of Tennessee's health insurance code.