1. Short title This Act may be cited as the Improving Health Insurance Affordability Act of 2023 . 2. Increase in eligibility for credit (a) In general Subparagraph (A) of section 36B(c)(1) of the Internal Revenue Code of 1986 is amended by striking but does not exceed 400 percent . (b) Applicable percentages (1) In general Subparagraph (A) of section 36B(b)(3) of the Internal Revenue Code of 1986 is amended to read as follows: (A) Applicable percentage The applicable percentage for any taxable year shall be the percentage such that the applicable percentage for any taxpayer whose household income is within an income tier specified in the following table shall increase, on a sliding scale in a linear manner, from the initial premium percentage to the final premium percentage specified in such table for such income tier: In the case of household income (expressed as a percent of poverty line) within the following income tier: The initial premium percentage is— The final premium percentage is— Up to 150 percent 0 0 150 percent up to 200 percent 0 2.0 200 percent up to 250 percent 2.0 4.0 250 percent up to 300 percent 4.0 6.0 300 percent up to 400 percent 6.0 8.5 400 percent and up 8.5 8.5. . (2) Conforming amendments relating to affordability of coverage (A) Subparagraph (C) of section 36B(c)(2) of such Code is amended by striking clause (iv). (B) Paragraph (4) of section 36B(c) of such Code is amended by striking subparagraph (F). (c) Limitation on recapture Clause (i) of section 36B(f)(2)(B) of the Internal Revenue Code of 1986 is amended— (1) by striking 400 percent and inserting 800 percent ; (2) by striking the period at the end of the last row of the table