Miss. Code § 27-65-53
If the commissioner finds that the taxpayer has overpaid his tax for any reason and the taxpayer has discontinued business and there is no subsequent liability upon which the excess may be credited, or if the amount of the excess so paid shall exceed the estimated liability for the next twelve (12) months, the excess shall be refunded to the taxpayer. Such amount shall be certified to the State Auditor of Public Accounts by the commission. The said auditor is hereby authorized to make such investigation and audit of the claim as he finds necessary. If he finds that the commissioner is correct in his determination, the auditor may issue his warrant to the State Treasurer in favor of the taxpayer for the amount of tax erroneously paid into the State Treasury, such refunds to be made from current sales tax collections. If part of the overpayment has been disbursed to any municipality or state institution of higher learning, under authority of Section 27-65-75, the municipality or state institution of higher learning, having erroneously received the money, shall adjust the amount with the commissioner, or the overpayment may be withheld by the state from any funds due by the state to the municipality or state institution of higher learning.
Provided, that where the taxpayer has overpaid his tax, the commissioner may give credit for same and allow the taxpayer to take credit on a subsequent return or, if necessary, in his discretion, have the taxpayer file for a refund as provided herein.
If any overpayment of tax as reflected in an application or amended return, or both, filed by the taxpayer, and verified by the commissioner or otherwise determined to be due by the commissioner or commission, is not refunded or credited to a taxpayer's account within ninety (90) days after the application or amended return is filed or the date the commission or commissioner determines a refund is due, whichever is later, interest at the rate of one-half of one percent (1/2 of 1%) per month shall be allowed on such overpayment computed for the period after expiration of the ninety-day period provided herein to the date of payment.
Miss. Code § 27-65-53