You can charge GST at 0% for your supply of goods when you are certain that at the point of supply (based on the
time of supply for exports) :
The goods supplied will be exported or have been exported; and
You have the required documents to support zero-rating.
Based on the export arrangement for the supply of goods, please review which scenario of
Guide on Exports (Seventh Edition) (PDF, 717KB) the arrangement falls within to determine the relevant list of documents that suppliers must maintain in order to support any zero-rating of the supply.