Car Expense Tax Deduction Calculator
Estimate your work-related car expense deduction with the ATO cents-per-km or log book method — and the tax you save.
Car Expense Tax Deduction Calculator
Estimate your work-related car expense deduction using the ATO cents-per-km or log book method, and the tax you save.
• Estimates only. Keep your log book and receipts — the ATO may ask to see them. Rates from 1 July 2025 are estimates.
Cents per Km Method
The ATO's cents-per-km method uses a set rate per work-related kilometre (92 cents from 1 July 2025, an estimate) and is capped at 5,000 work kilometres. No receipts are needed — just the kilometres and a reasonable basis for them.
Log Book Method
The log book method requires a 12-week log book showing your business use percentage, plus receipts for all car expenses (fuel, registration, insurance, servicing, depreciation). Your deduction is total expenses × business percentage. It usually gives a bigger deduction for high-mileage drivers.
Which Method Should You Use?
Use the cents-per-km method if you drive under 5,000 work kilometres and want simplicity. Use the log book method if you drive more or have high car expenses — the calculator lets you compare both.
Frequently Asked Questions
What is the ATO rate per km for 2025-26?
The rate is an estimated 92 cents per kilometre from 1 July 2025 (confirm with the ATO). The cents-per-km method is capped at 5,000 work kilometres.
Do I need receipts for the cents-per-km method?
No, but you need to show how you worked out the work kilometres. The log book method does require receipts and a 12-week log book.
Can I claim commuting to work?
Generally no — travel between home and work is private, not deductible, unless you have a home office and travel to different sites.
How much tax will I save?
Your deduction reduces your taxable income, saving your marginal tax rate on that amount. The calculator estimates the saving automatically.