Published: 4 March 2026

KM Allowance Tax Deduction Australia: How to Claim Car Expenses

If you use your personal vehicle for work-related travel, you could be missing out on valuable tax deductions. Understanding how the kilometre (km) allowance tax deduction works in Australia can help you reduce your taxable income and increase your tax refund. Whether you're visiting clients, attending meetings off-site, or transporting work equipment, knowing what you can claim and how to calculate it properly is essential for every Australian worker.

The Australian Taxation Office (ATO) allows eligible employees and self-employed individuals to claim deductions for work-related car expenses. The good news is that you don't need to be a tax expert to take advantage of these deductions — with the right information and record-keeping, claiming your km allowance can be straightforward. In this guide, we'll break down everything you need to know about claiming car expenses on your tax return for the 2025-26 financial year.

What Is a KM Allowance Tax Deduction?

A km allowance tax deduction allows you to claim expenses incurred when using your personal vehicle for work purposes. This is different from receiving a car allowance from your employer — which is taxable income added to your salary. Instead, this deduction covers the actual costs of work-related travel, including fuel, registration, insurance, and depreciation.

The ATO recognises that many Australian workers need to use their cars for work, from tradies carrying tools between job sites to sales representatives visiting clients. By claiming legitimate work-related car expenses, you can significantly reduce your taxable income and improve your overall financial position. Understanding the difference between deductible work travel and personal travel is crucial to staying compliant while maximising your legitimate claims.

The Two Methods for Claiming Car Expenses

The ATO provides two distinct methods for calculating and claiming work-related car expenses. Choosing the right method for your situation can make a substantial difference to your tax deduction amount. You can select whichever method gives you the larger deduction, but you must have the appropriate records to support your claim.

Method 1: Cents Per Kilometre

The cents per kilometre method is the simplest approach and requires minimal record-keeping. Under this method, you can claim a set rate for each work-related kilometre travelled, up to a maximum of 5,000 kilometres per year per vehicle. For the 2025-26 financial year, the ATO has set the rate at 88 cents per kilometre.

This means the maximum deduction you can claim using this method is $4,400 (5,000 km × $0.88). While you don't need to keep receipts for individual expenses, you do need to be able to demonstrate how you calculated your work-related kilometres. A diary or log showing the date, purpose, and distance of work trips is typically sufficient evidence.

Method 2: Logbook Method

The logbook method requires more detailed record-keeping but can result in a larger deduction if you travel significant distances for work or have high vehicle running costs. Under this method, you must maintain a valid logbook for a continuous 12-week period that represents your typical travel patterns. Your logbook is then valid for five years.

Using this method, you calculate the work-related percentage of your total vehicle expenses. This includes fuel, oil, registration, insurance, repairs, servicing, depreciation (decline in value), and interest on your car loan. If your work travel percentage is high, this method often produces a more substantial tax benefit than the cents per kilometre approach.

ATO Car Expense Rates for FY 2025-26

Understanding the current rates and thresholds is essential for accurate tax planning. Here's a summary of the key figures for the 2025-26 financial year:

The 88 cents per kilometre rate covers all vehicle running costs, so you cannot claim additional expenses like fuel or servicing separately when using this method. The rate is designed to account for the average costs of owning and operating a vehicle in Australia, including fuel, maintenance, registration, and depreciation.

What Travel Can You Claim?

Understanding what constitutes deductible work-related travel is crucial for staying compliant with ATO requirements. You can generally claim travel between different workplaces, from your home to an alternative workplace (like a client meeting), and between job sites. If you carry bulky tools or equipment that your employer requires you to transport and there's no secure storage at work, your travel from home may also be deductible.

However, you cannot claim travel from home to your regular place of work — this is considered private travel. Similarly, detours for personal reasons during work trips, travel during unpaid meal breaks, and trips after work hours for personal purposes are not deductible. Being clear about these distinctions helps you claim correctly and avoid issues during an ATO review.

Record-Keeping Requirements

Good record-keeping is essential for any tax deduction claim. For the cents per kilometre method, you need a diary or log that shows the dates, purpose, and distances of your work trips. While you don't need receipts for individual expenses, you should be able to explain how you calculated your kilometres if asked.

For the logbook method, your records must include a properly maintained logbook covering at least 12 continuous weeks, all receipts and invoices for car expenses (fuel, servicing, registration, insurance), and documentation showing how you calculated the business use percentage. Keeping organised records throughout the year makes tax time much easier and ensures you don't miss any legitimate deductions.

Impact on Your Tax and Take-Home Pay

Claiming car expenses can have a meaningful impact on your tax situation. For example, if you're in the 30% tax bracket and claim the maximum $4,400 deduction using the cents per kilometre method, you could receive a tax refund of approximately $1,320. If you have a HECS-HELP debt, remember that while deductions reduce your taxable income, your HECS repayment income is calculated differently and may not be reduced by the same amount.

Car expense deductions also affect your Medicare levy calculation, as the 2% levy is applied to your taxable income after deductions. For higher income earners, reducing your taxable income through legitimate deductions may also help you avoid the Medicare Levy Surcharge. You can use our take-home pay calculator to estimate how different deduction scenarios might affect your overall financial position.

Special Considerations for Different Workers

Different types of workers have unique considerations when claiming car expenses. Tradies and construction workers often have significant work-related travel between job sites and may benefit more from the logbook method. Sales representatives and consultants who frequently visit clients may easily reach the 5,000 km cap and should consider which method maximises their deduction.

Self-employed individuals and freelancers can also claim car expenses, though the record-keeping requirements remain the same. If you use your vehicle for both business and personal purposes, accurate apportionment is essential. Consider using a dedicated car expense tracking app to simplify your record-keeping throughout the financial year.

Maximising Your Car Expense Deductions

To get the most from your car expense deductions, start by tracking your work-related kilometres from the beginning of the financial year. Even if you're unsure which method you'll use at tax time, having a record of your work travel gives you options. If your work-related percentage is likely to exceed the equivalent of 5,000 km at 88 cents per km (which is about 35% for the average driver), seriously consider the logbook method.

Don't forget that other work-related travel expenses may also be deductible, such as parking fees, tolls, and public transport costs. These can be claimed in addition to your car expenses. If you receive a car allowance from your employer, this is taxable income and should be included in your income tax return, but you can still claim actual car expenses as deductions — potentially leading to a significant tax benefit.

Common Mistakes to Avoid

Many taxpayers make errors when claiming car expenses that can lead to denied deductions or ATO scrutiny. Common mistakes include claiming travel between home and a regular workplace, not keeping adequate records, claiming over the 5,000 km cap using the cents per kilometre method, and not maintaining a valid logbook for the logbook method. Another error is claiming a deduction for a vehicle provided by your employer — if your employer owns or leases the car, you generally cannot claim expenses for it.

If you've made genuine errors in previous tax returns, the ATO may allow amendments. However, it's always better to get it right the first time by understanding the rules and keeping proper documentation throughout the year.

Summary

Claiming kilometre allowance tax deductions is a legitimate way for Australian workers to reduce their taxable income when they use their personal vehicles for work purposes. For the 2025-26 financial year, the cents per kilometre rate of 88 cents per km provides a simple option for those with moderate work travel, while the logbook method offers potentially larger deductions for those with significant work-related vehicle use.

The key to maximising your car expense deductions is understanding which method works best for your situation, keeping accurate records throughout the year, and ensuring you only claim legitimate work-related travel. Whether you're an employee travelling between sites, a freelancer visiting clients, or a tradie carrying equipment to job locations, taking the time to properly claim your car expenses can deliver meaningful tax savings.

Remember that tax deductions work alongside other elements of your financial picture, including superannuation contributions, salary sacrifice arrangements, and your overall tax strategy. By staying informed about your entitlements and keeping good records, you can make the most of every legitimate deduction available to you.