(a) As provided in this Code section, each county and municipality shall refund to taxpayers any and all taxes and license fees:

(1) Which are determined to have been erroneously or illegally assessed and collected from the taxpayers under the laws of this state or under the resolutions or ordinances of any county or municipality; or

(2) Which are determined to have been voluntarily or involuntarily overpaid by the taxpayers.

(a.1) If property owners have been billed and have remitted property tax payments to either a county or a municipality based on the fair market value of the land and subsequently the fair market value of such land is reduced on an appeal, then the county or the municipality shall reimburse the property owner the difference between tax remitted and the final tax owed for each year in which the incorrect fair market value of the land was used in the calculations.

(b) Any taxpayer from whom a tax or license fee was collected who alleges that such tax or license fee was collected illegally or erroneously may file a claim for a refund with the governing authority of the county or municipality at any time within one year or, in the case of taxes, three years after the date of the payment of the tax or license fee to the county or municipality. The claim for refund shall be in writing and shall be in the form and shall contain the information required by the appropriate governing authority. The claim shall include a summary statement of the grounds upon which the taxpayer relies. In the event the taxpayer desires a conference or hearing before the governing authority in connection with any claim for a refund, the taxpayer shall so specify in writing in the claim. If the claim conforms to the requirements of this Code section, the governing authority shall grant a conference at a time specified by the governing authority. The governing authority shall consider information contained in the taxpayer's claim for a refund and such other information as is available. The governing authority shall approve or disapprove the taxpayer's claim and shall notify the taxpayer of its action. In the event any claim for refund is approved, the governing authority shall proceed under subsection (a) of this Code section to give effect to the terms of that subsection. No refund provided for in this Code section shall be assignable. Submitting a request for refund to the governing authority is not a prerequisite to bringing suit.

(c) The filing of a request for a refund with the governing authority under subsection (b) of this Code section shall act to stay the time period for initiating suit for a refund. Following the filing of a request for refund with the governing authority, no suit may be commenced until the earlier of the governing authority's denial of the request for refund or the expiration of 90 days from the date of filing the claim. Alternatively, any taxpayer may forgo requesting a refund from the governing authority under subsection (b) of this Code section and elect to proceed directly to filing suit.

(d) Any refunds approved or allowed under this Code section shall be paid from funds of the county, the municipality, the county board of education, the state, or any other entity to which the taxes or license fees were originally paid. Refunds shall be paid within 60 days of the approval of the taxpayer's claim or within 60 days of the entry of a final decision in any action for a refund.

(e) The governing authority of any county, by resolution, and the governing authority of any municipality, by ordinance, shall adopt rules and regulations governing the administration of this Code section and may delegate the administration of this Code section, including the approval or disapproval of claims where the reason for the claim is based on an obvious clerical error, to an appropriate department in local government. In disputed cases where there is no obvious error, the approval or disapproval of claims may not be delegated by the governing authority.

(f) Nothing contained in subsections (b) or (c) of this Code section shall be deemed the exclusive remedy to seek a refund nor deprive taxpayers of the right to seek a refund mandated by subsection (a) by any other cause of action available at law or equity.

(g) Under no circumstances may a suit for refund be commenced more than five years from the date of the payment of taxes or fees at issue.