Under the Continuing Appropriations Act, 2021 and Other Extensions Act, repayment will now begin one year from the issuance date of each provider or supplier’s accelerated or advance payment. After that first year, Medicare will automatically recoup 25 percent of Medicare payments otherwise owed to the provider or supplier for eleven months. At the end of the eleven-month period, recoupment will increase to 50 percent for another six months. If the provider or supplier is unable to repay the total amount of the accelerated or advance payment during this time-period (a total of 29 months), CMS will issue demand letters requiring repayment of any outstanding balance, subject to an interest rate of four percent consistent with the Continuing Appropriations Act, 2021.
https://www.cms.gov/medicare/covid-19-accelerated-and-advance-payments