O.C.G.A. § 48-7-80 (2019)

The total amount of tax imposed by this chapter on taxpayers other than corporations shall be paid to the commissioner on or before April 15 following the close of the calendar year. If the return of a taxpayer other than a corporation is made on the basis of a fiscal year, the tax shall be paid to the commissioner on or before the fifteenth day of the fourth month following the close of the fiscal year. However, in the case a taxpayer’s return is allowed to be filed at a later date, pursuant to the Internal Revenue Code of 1986 as it existed on or after January 1, 2003, because the taxpayer has electronically filed returns, the date of payment shall be extended without interest and penalty to the date the return is allowed to be filed pursuant to the Internal Revenue Code of 1986 as it existed on or after January 1, 2003. The total amount of tax imposed by this chapter on corporations other than Georgia Subchapter “S” corporations shall be paid to the commissioner on or before April 15, following the close of the calendar year. If the return of a corporation other than a Georgia Subchapter “S” corporation is made on the basis of a fiscal year, the tax shall be paid to the commissioner on or before the fifteenth day of the fourth month following the close of the fiscal year. The total amount of tax imposed by this chapter on Georgia Subchapter “S” corporations shall be paid to the commissioner on or before March 15, following the close of the calendar year. If the return of a Georgia Subchapter “S” corporation is made on the basis of a fiscal year, the tax shall be paid to the commissioner on or before the fifteenth day of the third month following the close of the fiscal year.