Forms related to Certificates of Exemption. ST-5 Certificate of Exemption.ST-5 Sales Tax Certificate of Exemption (PDF, 166.41 KB). This is a multi-state form. Not all states allow all exemptions listed on this form. Complete Form W-4 so that your employer can withhold the correct federal income tax from your pay. Give Form W-4 to your employer. You can not claim exempt if you did not file a Georgia income tax return for the previous tax year. Failure to properly and timely file the application constitutes a waiver of the exemption for that year. Deadline for filing Homestead exemption (including Disability Exemption or Age Exemption) is April 1st.