Tax Tip: keep All Receipts forever By law you are only required to keep receipts for about 7 years. But this is 7 years after you claim an expense. You should always keep your receipts just in case. If you move out of the main residence and rent it at some stage then the expenses incurred when you were living there can be used to reduce the CGT payable. When someone dies and their property is inherited by someone else the cost base of the deceased will often be the cost base of the property for the person that inherited the property. So expenses incurred when the deceased was alive and living there or renting the property out can be relevant to the tax of the person that inherited the property.