O.C.G.A. § 21-2-490 (2019)

(a) Each superintendent shall cause his or her office to remain open during the entire duration of each primary and election and after the close of the polls, until all the ballot boxes and returns have been received in the office of the superintendent or received in such other place as has been designated by him or her. (b) The chairperson of the county board of registrars shall cause his or her office to remain open during the entire duration of each primary and election and after the close of the polls, until completion of the duties of said board. The provisions of this subsection shall not apply with respect to such offices in counties of this state having a population of 550,000 or more according to the United States decennial census of 1970 or any future such census.