Ga. Const. art. IX, § 4, para. 1

(a) Except as otherwise provided in this Paragraph, the governing authority of any county, municipality, or combination thereof may exercise the power of taxation as authorized by this Constitution or by general law.

(b) In the absence of a general law:

(1) County governing authorities may be authorized by local law to levy and collect business and occupational license taxes and license fees only in the unincorporated areas of the counties. The General Assembly may provide that the revenues raised by such tax or fee be spent for the provision of services only in the unincorporated areas of the county.

(2) Municipal governing authorities may be authorized by local law to levy and collect taxes and fees in the corporate limits of the municipalities.

(c) The General Assembly may provide by law for the taxation of insurance companies on the basis of gross direct premiums received from insurance policies within the unincorporated areas of counties. The tax authorized herein may be imposed by the state or by counties or by the state for county purposes as may be provided by law. The General Assembly may further provide by law for the reduction, only upon taxable property within the unincorporated areas of counties, of the ad valorem tax millage rate for county or county school district purposes or for the reduction of such ad valorem tax millage rate for both such purposes in connection with imposing or authorizing the imposition of the tax authorized herein or in connection with providing for the distribution of the proceeds derived from the tax authorized herein.