42 CFR § 431.220 - When a hearing is required.
(a) The State agency must grant an opportunity for a hearing to the following:
(1) Any individual who requests it because he or she believes the agency has taken an action erroneously, denied his or her claim for eligibility or for covered benefits or services, or issued a determination of an individual's liability, or has not acted upon the claim with reasonable promptness including, if applicable -
(i) An initial or subsequent decision regarding eligibility;
(iii) A determination of the amount of premiums and cost sharing charges under subpart A of part 447 of this chapter;
(iv) A change in the amount or type of benefits or services; or
(v) A request for exemption from mandatory enrollment in an Alternative Benefit Plan.
(3) Any individual who requests it because he or she believes the State has made an erroneous determination with regard to the preadmission and annual resident review requirements of section 1919(e)(7) of the Act.
(4) Any MCO, PIHP, or PAHP enrollee who is entitled to a hearing under subpart F of part 438 of this chapter.
(6) Any enrollee who is entitled to a hearing under subpart B of part 438 of this chapter.
(b) The agency need not grant a hearing if the sole issue is a Federal or State law requiring an automatic change adversely affecting some or all beneficiaries.