42 CFR § 436.406 - Citizenship and alienage.
(a) The agency must provide Medicaid to otherwise eligible residents of the United States who are—
(1) Citizens: (i) Under a declaration required by section 1137(d) of the Act that the individual is a citizen or national of the United States; and
(ii) The individual has provided satisfactory documentary evidence of citizenship or national status, as described in § 435.407.
(iii) An individual for purposes of the declaration and citizenship documentation requirements discussed in paragraphs (a)(1)(i) and (a)(1)(ii) of this section includes both applicants and beneficiaries under a section 1115 demonstration (including a family planning demonstration project) for which a State receives Federal financial participation in their expenditures, as though the expenditures were for medical assistance.
(iv) Individuals must declare their citizenship and the State must document an individual's eligibility file on initial applications and initial redeterminations effective July 1, 2006.
(v) The following groups of individuals are exempt from the requirements in paragraph (a)(1)(ii) of this section:
(A) Individuals receiving SSI benefits under title XVI of the Act;
(B) Individuals entitled to or enrolled in any part of Medicare;
(C) Individuals receiving disability insurance benefits under section 223 of the Act or monthly benefits under section 202 of the Act, based on the individual's disability (as defined in section 223(d) of the Act); and
(D) Individuals who are in foster care and who are assisted under Title IV–B of the Act, and individuals who are beneficiaries of foster care maintenance or adoption assistance payments under Title IV-E of the Act.
(2)
(i) Except as specified in 8 U.S.C. 1612(b)(1) (permitting States an option with respect to coverage of certain qualified aliens), qualified aliens as described in section 431 of the Personal Responsibility and Work Opportunity Reconciliation Act of 1996 (8 U.S.C. 1641) (including qualified aliens subject to the 5-year bar) who have provided satisfactory documentary evidence of Qualified Alien status, which status has been verified with the Department of Homeland Security (DHS) under a declaration required by section 1137(d) of the Act that the applicant or beneficiary is an alien in a satisfactory immigration status.
(ii) The eligibility of qualified aliens who are subject to the 5-year bar in 8 U.S.C. 1613 is limited to the benefits described in paragraph (b) of this section.
(b) The agency must provide payment for the services described in § 440.255(c) of this chapter to residents of the State who otherwise meet the eligibility requirements of the State plan (except for receipt of AFDC, SSI, or State Supplementary payments) who are qualified aliens subject to the 5-year bar or who are non-qualified aliens who meet all Medicaid eligibility criteria, except non-qualified aliens need not present a social security number or document immigration status.