Miss. Code § 27-7-20
Casualty losses of individuals shall be computed and allowed in accordance with the provisions of the Internal Revenue Code, rules, regulations and revenue procedures relating to casualty and theft losses and disaster losses not in direct conflict with the provisions of the Mississippi Income Tax Law.
The State Tax Commission shall apply a special rule with respect to any loss attributable to a disaster occurring in an area subsequently determined by the President of the United States to warrant assistance by the federal government under the Disaster Relief Act of 1974. In lieu of the net operating loss carryover provision, a "net casualty loss" deduction may result when itemized deductions, including the original casualty loss, exceed gross income. The "net casualty loss" shall be computed with the following modifications:
The "net casualty loss" is allowed as a deduction from gross income and may be carried back to each of the three (3) years preceding the tax year in which the original casualty loss is claimed or as otherwise provided under the Internal Revenue Code. If the net casualty loss deduction is not exhausted within the three (3) preceding years or as otherwise provided under the Internal Revenue Code, any net casualty loss remaining shall be carried over to each of the seven (7) years following the tax year in which the original casualty loss is claimed. In determining the amount of any net casualty loss carryback or carryover to any tax year, the necessary computations involving any other tax year shall be made under the law applicable to such other tax year.
Miss. Code § 27-7-20