Where both spouses itemize deductions, the deductions must be divided between them in the ratio that each spouse's separate Iowa net income bears to the total Iowa net income of both spouses unless each spouse can show that the spouse paid for or is entitled to accrue the deductions. It will be presumed that the deductions are paid by both spouses and must be prorated if the deductions were paid from a joint checking account of both spouses. In any event, all itemized deductions must either be prorated between spouses or must be specifically deducted by the spouse that paid for the deductions. No combinations of the two methods will be permitted.
This rule is intended to implement Iowa Code section 4229..
Iowa Admin. Code r. 701-41.6