CGT records for property investors: what to keep, and for how long

Keep every document that proves the five elements of the property’s CGT cost base — the purchase price, incidental costs of buying and selling (stamp duty, legal fees, agent’s commission, borrowing expenses), non-deductible costs of owning, capital improvement costs and costs of defending title — together with records showing whether each expense was claimed as a tax deduction. Keep them for at least 5 years after you dispose of the property (longer where capital losses are carried forward), because amounts you cannot substantiate generally cannot reduce the capital gain, and penalties can apply for failing to keep records.

Key points:
- Your records must prove all five elements of the [cost base](/technical-resources/glossary#cost-base) — acquisition cost, incidental costs of buying and selling, non-deductible costs of owning, capital improvements and title defence costs — per the [ATO’s cost base guidance](https://www.ato.gov.au/individuals-and-families/investments-and-assets/capital-gains-tax/calculating-your-cgt/cost-base-of-asset) updated 29 June 2026.
- The ATO’s property record list covers the purchase contract, stamp duty, legal fees, settlement statements, survey and valuation fees, the sale contract, sales commission, holding-cost receipts and capital improvement invoices.
- Keep everything for at least **5 years after you dispose of the property** — because the records start at purchase, a 10-year hold means roughly 15 years of records, and carried-forward capital losses extend the clock.
- No double dipping: amounts you claimed (or could claim) as deductions stay out of the cost base — which makes depreciation schedules and past tax returns core CGT records, with capital works deductions subtracted in the ATO’s own rental-property example.
- The CGT event happens on the contract date, not at settlement — and since 1 January 2025, Australian-resident vendors need an ATO clearance certificate at or before settlement or the purchaser must withhold up to 15% of the sale proceeds.
- Missing records have real consequences: in the ATO’s words you may end up paying more tax than necessary, unsupported claims can be disallowed on review, and penalties can apply for failing to keep or retain records.
- **Schedule 1 of the [Treasury Laws Amendment (Tax Reform No. 1) Act 2026](https://www.legislation.gov.au/C2026A00049/asmade) makes records *more* important, not less.** For CGT events on or after 1 July 2027, the discount percentage for resident individuals and non-superannuation trusts on ordinary assets becomes 0%, and cost-base indexation is available instead where the Division 114 requirements are met — but indexation runs only on expenditure incurred on or after 1 July 2027 (s 960-275(1B)), so the **date** each cost was incurred now carries consequences of its own.