45 CFR §155.350

1. (a)Eligibility for cost-sharing reductions.
   1. (1)The Exchange must determine an applicant who is an Indian eligible for cost-sharing reductions if he or she—
      1. (i)Meets the requirements specified in § 155.305(a) and § 155.305(f);
      2. (ii)Is expected to have a household income, as defined in 26 CFR 1.36B-1(e) that does not exceed 300 percent of the FPL for the benefit year for which coverage is requested.
   2. (2)The Exchange may only provide cost-sharing reductions to an individual who is an Indian if he or she is enrolled in a QHP through the Exchange.
2. (b)Special cost-sharing rule for Indians regardless of income. The Exchange must determine an applicant eligible for the special cost-sharing rule described in section 1402(d)(2) of the Affordable Care Act if he or she is an Indian, without requiring the applicant to request an eligibility determination for insurance affordability programs in accordance with § 155.310(b) in order to qualify for this rule.
3. (c)Verification related to Indian status. To the extent that an applicant attests that he or she is an Indian, the Exchange must verify such attestation by—
   1. (1)Utilizing any relevant documentation verified in accordance with § 155.315(f);
   2. (2)Relying on any electronic data sources that are available to the Exchange and which have been approved by HHS for this purpose, based on evidence showing that such data sources are sufficiently accurate and offer less administrative complexity than paper verification; or
   3. (3)To the extent that approved data sources are unavailable, an individual is not represented in available data sources, or data sources are not reasonably compatible with an applicant's attestation, the Exchange must follow the procedures specified in § 155.315(f) and verify documentation provided by the applicant in accordance with the standards for acceptable documentation provided in section 1903(x)(3)(B)(v) of the Social Security Act.