; enrollment periods (1) In general A State that has elected to allow individuals to buy into Medicaid coverage under section 1902(a)(10)(A)(ii)(XXIII) of the Social Security Act ( 42 U.S.C. 1396a(a)(10)(A)(ii)(XXIII) ) shall allow individuals to enroll in such coverage through the Federal, Federally-facilitated, or State Exchange established pursuant to title I of the Patient Protection and Affordable Care Act. (2) Enrollment periods A State may limit the enrollment of individuals into Medicaid coverage under section 1902(a)(10)(A)(ii)(XXIII) of the Social Security Act ( 42 U.S.C. 1396a(a)(10)(A)(ii)(XXIII) ) to the enrollment periods provided for under section 1311(c)(6) of the Patient Protection and Affordable Care Act ( 42 U.S.C. 18031(c)(6) ). (g) Application of advanced premium tax credits to Medicaid buy-In plans (1) In general Section 36B of the Internal Revenue Code of 1986 is amended— (A) in subsection (b)(3)(B), by adding at the end the following new sentence: If an applicable taxpayer resides in a rating area in which no silver plan is offered on the individual market but the taxpayer buys into Medicaid coverage under section 1902(a)(10)(A)(ii)(XXIII) of the Social Security Act, such Medicaid coverage shall be deemed to be the applicable second lowest cost silver plan with respect to such taxpayer.