O.C.G.A. § 45-5-5: To whom resignations to be made.

(a) The resignations of all state and county officers and senators and representatives of the State of Georgia in the United States Congress shall be made to the Governor. If the resignation is from an office which may not be filled by executive appointment of the Governor, the Governor shall, upon receiving the resignation, promptly notify the appropriate official of the state or county to fill the vacancy or to initiate the process for filling the vacancy according to law.

(b) The resignations of municipal officers shall be made to the governing authority of the municipality who shall fill the vacancies in accordance with law.