You need to keep records that show the income and expenses used to calculate and support the amounts you report and claim for GST credits. This includes all sales, tax invoices and other GST-related transactions, fees, expenses, wages and any other business costs. 

You must keep any other documents that record adjustments, a decision or a calculation made for GST purposes. 

If your records don't adequately support your claims, the ATO may adjust or deny some claims, so it's important to keep the right records and to get your calculations right. 

It’s recommended that you set aside your GST in a separate ledger account to make your record-keeping and calculations easier. 

You don’t need a tax invoice to claim GST credits for taxable imports (goods your business imports into Australia). However, to meet the record-keeping requirements, you must have documents from the Department of Home Affairs showing the amount of GST you paid on those imports. 

How long you need to keep GST records

You need to keep your GST records for 5 years, starting from when you prepared or obtained the records, or when you completed the transactions the records relate to, whichever is later.

You should keep records long enough to cover the period of review (also known as the amendment period) for an assessment that uses information from the record.