If you make a mistake (that fits the definition of a GST error) when reporting GST on an earlier BAS (business activity statement), you can correct that error on a later BAS if you meet certain conditions.
Generally, it is easier to correct a GST error on a later BAS than to revise an earlier period. Revising an earlier period that contains an error can incur penalties or general interest charge (GIC).
You can only correct a GST error in a later BAS, if the later BAS is lodged during the period of review for the earlier period in which the error was made.
You cannot correct an error to claim additional GST credits where the 4-year credit time limit for claiming those GST credits has expired.