1. Short title This Act may be cited as the Transparency in Billing Act of 2023 . 2. Honest billing requirements (a) In general Subpart B of part 7 of subtitle B of title I of the Employee Retirement Income Security Act of 1974 ( 29 U.S.C. 1185 et seq. ) is amended by adding at the end the following new section: 726. Honest billing requirements A group health plan or health insurance issuer offering group health insurance coverage may not pay a claim for items and services furnished to an individual at an off-campus outpatient department of a provider (as defined in section 901(c)) submitted by a hospital (as defined in section 1861(e) of the Social Security Act) unless such claim submitted by such hospital includes the separate unique health identifier for the department where items and services were furnished, in accordance with section 901. . (b) Clerical amendment The table of contents of the Employee Retirement Income Security Act of 1974 ( 29 U.S.C. 1001 note) is amended by adding after the item relating to section 725 the following: Sec. 726. Honest billing requirements. . (c) Effective date The amendments made by this section shall take effect with respect to plan years beginning on or after January 1, 2024. 3. Regulation of honest billing (a) In general Subtitle B of title I of the Employee Retirement Income Security Act of 1974 ( 29 U.S.C. 1021 et seq. ) is amended by adding at the end the following new part: 9 Billing Requirements with Respect to Group Health Plans and Coverage 901. Honest billing requirements (a) In general A hospital may not, with respect to items and services furnished to an individual at an off-campus outpatient department of a provider, submit a claim for such items and services to a group health plan or health insurance issuer, and may not hold such individual liable for such items and services, unless— (1) such hospital obtains a separate unique health identifier established for such department pursuant to section 1173(b) of the Social Security Act