O.C.G.A. § 48-13-77 (2019)

Each corporation other than Georgia Subchapter “S” corporations subject to the tax imposed by this article shall file a return and pay the tax due on the fifteenth day of the fourth calendar month following the beginning of its tax period. Each Georgia Subchapter “S” corporation subject to the tax imposed by this article shall file a return and pay the tax due on the fifteenth day of the third calendar month following the beginning of its tax period. The commissioner may authorize combining the return required by this Code section with the state income tax return required by law. The return shall be signed and sworn to by an officer of the corporation and shall be forwarded to the commissioner.