1. Short title This Act may be cited as the Know the Lowest Price Act of 2018 . 2. Prohibition on limiting certain information on drug prices (a) In general Section 1860D–4 of the Social Security Act ( 42 U.S.C. 1395w–104 ) is amended by adding at the end the following new subsection: (m) Prohibition on limiting certain information on drug prices A PDP sponsor and a Medicare Advantage organization shall ensure that— (1) any health benefits plan offered by the sponsor or organization, including a prescription drug plan and an MA–PD plan, does not restrict a pharmacy that dispenses a prescription drug or biological from informing (or penalize such pharmacy for informing) an enrollee of any differential between the price of the drug or biological to the enrollee under the plan and the price the individual would pay for the drug or biological if the enrollee obtained the drug without using any health insurance coverage; and (2) any entity that provides pharmacy benefits management services under a contract with any health benefits plan offered by the sponsor or organization does not, with respect to such plan or any health benefits plan that the entity contracts with to provide pharmacy benefits management services and that is offered by an entity other than such sponsor or organization, restrict a pharmacy that dispenses a prescription drug or biological from informing (or penalize such pharmacy for informing) an enrollee of any differential between the price of the drug or biological to the enrollee under the plan and the price the individual would pay for the drug or biological if the enrollee obtained the drug without using any health insurance coverage. . (b) Effective date The amendment made by subsection (a) shall apply to plan years beginning on or after January 1, 2020.