Miss. Code § 27-9-45
If no return is made by an executor required to make returns, as provided herein, the commissioner shall give written notice by mail to such executor to make such returns within thirty (30) days from the date of such notice and if such executor shall fail or refuse to make such returns as he may be required to make in such notice, then such return shall be made by the commissioner from the best information available and such return shall be prima facie correct for the purposes of this chapter, and the amount of tax shown due thereby shall be a lien against all the property of the decedent until discharged by payment and if any payment be not made within sixty (60) days after the demand therefor by the commissioner, there shall be added fifty percent (50%) as damages, together with interest at the rate of one percent (1%) per month on the tax from the time such tax was due. If such tax be paid within sixty (60) days after notice by the commissioner, then there shall be added ten percent (10%) as damages and interest at the rate of one percent (1%) from the time such tax was due until paid; however, in the event the executor in answer to the notice from the commissioner shall state that he is not required under the law to make such returns, the commissioner shall investigate that question fully before proceeding further under this section.
The commissioner's authority to make collection of estate tax shall be determined at the end of four (4) years from the date of filing of estate tax return, but in the event that no return is filed, the commissioner's authority to make a return from any information available at that time shall be terminated at the end of ten (10) years from the due date of the return.
In the event the federal estate tax or any part thereof is being contested with the federal government, the commissioner's right to make an additional assessment based on final determination of the federal estate tax assessment shall be in force for a period of two (2) years after the determination.
Miss. Code § 27-9-45