42 CFR §457.1130

1. (a)Eligibility or enrollment matter. A State must ensure that an applicant or enrollee has an opportunity for review, consistent with §§ 457.1140 and 457.1150, of a—
   1. (1)Denial of eligibility;
   2. (2)Failure to make a timely determination of eligibility; and
   3. (3)Suspension or termination of enrollment, including disenrollment for failure to pay cost sharing.
2. (b)Health services matter. A State must ensure that an enrollee has an opportunity for external review of a—
   1. (1)Delay, denial, reduction, suspension, or termination of health services, in whole or in part, including a determination about the type or level of services; and
   2. (2)Failure to approve, furnish, or provide payment for health services in a timely manner.
3. (c)Exception. A State is not required to provide an opportunity for review of a matter described in paragraph (a) or (b) of this section if the sole basis for the decision is a provision in the State plan or in Federal or State law requiring an automatic change in eligibility, enrollment, or a change in coverage under the health benefits package that affects all applicants or enrollees or a group of applicants or enrollees without regard to their individual circumstances.