42 CFR § 422.314 - Special rules for beneficiaries enrolled in MA MSA plans.
(a) Establishment and designation of medical savings account (MSA). A beneficiary who elects coverage under an MA MSA plan—
(1) Must establish an MA MSA with a trustee that meets the requirements of paragraph (b) of this section; and
(2) If he or she has more than one MA MSA, designate the particular account to which payments under the MA MSA plan are to be made.
(b) Requirements for MSA trustees. An entity that acts as a trustee for an MA MSA must—
(1) Register with CMS;
(2) Certify that it is a licensed bank, insurance company, or other entity qualified, under sections 408(a)(2) or 408(h) of the Internal Revenue Code of 1986, to act as a trustee of individual retirement accounts;
(3) Agree to comply with the MA MSA provisions of section 138 of the Internal Revenue Code of 1986; and
(4) Provide any other information that CMS may require.
(c) Deposit in the MA MSA.
(1) The payment is calculated as follows:
(i) The monthly MA MSA premium is compared with 1/12 of the annual capitation rate applied under this section for the.
(ii) If the monthly MA MSA premium is less than 1/12 of the annual capitation rate applied under this section for the area, the difference is the amount to be deposited in the MA MSA for each month for which the beneficiary is enrolled in the MSA plan.
(2) CMS deposits the full amount to which a beneficiary is entitled under paragraph (c)(1)(ii) of this section for the calendar year, beginning with the month in which MA MSA coverage begins.
(3) If the beneficiary's coverage under the MA MSA plan ends before the end of the calendar year, CMS recovers the amount that corresponds to the remaining months of that year.