Georgia Code Title 34. Labor and Industrial Relations § 34-6-26

(a) It shall be unlawful for any employer to contract with any labor organization and for any labor organization to contract with any employer for the deduction of any fee, assessment, or other sum of money whatsoever from the wages or other earnings of an employee to be held for or to be paid over to a labor organization except upon the condition to be embodied in such contract that such deduction will be made only on the written authorization of the employee. Such authorization may be revoked at any time at the request of the employee.

(b) Nothing in this Code section shall be construed to impair any contract, agreement, or collective bargaining agreement in existence prior to July 1, 2013.