Iowa Code § 445.60: Refunding erroneous tax.

The board of supervisors shall direct the county treasurer to refund to the taxpayer any tax or portion of a tax found to have been erroneously or illegally paid, with all interest, fees, and costs actually paid. A refund shall not be ordered or made unless a claim for refund is presented to the board within two years of the date the tax was due, or if appealed to the board of review, the property assessment appeal board, director of revenue, or district court, within two years of the final decision.