The Fine Print Australia · PUBLISHED 27 JUN 2026 · VERIFIED 27 JUN 2026 · AU EDITION

ATO Car Expense Claim Methods: Logbook Can Beat Cents Per Km 🇦🇺

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If you drive 5,000 km for work in a year, using the logbook method instead of cents per kilometre could more than double your deduction — from $4,400 to around $9,000 for a typical mid-range car with high business use, depending on actual running costs and business-use percentage.

The number that matters

$4,400 — maximum annual car deduction an employee can claim using the ATO cents per kilometre method, based on the 88 cents per km rate and the 5,000 km cap per car, per year, 2024–25/2025 income years.

How it quietly costs you

Mechanism: Choosing the wrong method (cents per km vs logbook) and missing deductions

• For a car you own or lease, employees, sole traders and partners can use either:
• Cents per kilometre method, or
• Logbook method.
• Under cents per kilometre, you:
• Claim a fixed rate per work-related kilometre
• Are capped at 5,000 km per financial year per car.
• ATO’s current rate (and widely reported for 2024–25 and 2025 income years) is $0.88 per business km, so the maximum deduction is: [ 5{,}000 \text{ km} \times <mark class=“fig”>$0.88 = <mark class=“fig”>$4{,}400 ]

Impact: How much money people leave on the table

• With logbook or actual costs methods, there is no cap on kilometres, and you can claim the business-use percentage of all actual car running costs (fuel, insurance, rego, servicing, interest, depreciation, etc.).

• Example: A typical employee with a mid-range car and high work use:

• Total annual car costs: say $12,000 (fuel, rego, insurance, servicing, tyres, depreciation — a realistic combined figure from tax practitioners’ worked examples, not a formal ATO benchmark).

• Business-use percentage from logbook: 75%.

• Logbook deduction: [ <mark class=“fig”>$12{,}000 \times 75% = <mark class=“fig”>$9{,}000 ]

• Cents per km deduction (capped): [ 5{,}000 \text{ km} \times <mark class=“fig”>$0.88 = <mark class=“fig”>$4{,}400 ]

• Difference: $4,600 extra deduction by using logbook instead of cents per km (in this scenario).

• NRMA explains that the logbook method is generally more suitable for those who cover more than 5,000 km annually because it lets you claim all car expenses at your business-use percentage.

• The ATO explicitly allows you to choose either method each year and even use different methods for different cars, so failing to switch when your circumstances change directly costs you deductions.

Old vs better:

• Old / default behaviour: Use cents per km because it’s simple, resulting in a maximum $4,400 deduction.
• Better: Use logbook if your actual costs × business-use % exceed $4,400 (which is common for higher kms or higher-cost vehicles), potentially increasing your deduction by thousands of dollars per year.

The second, compounding trap

Mechanism: Missing or incomplete records that invalidate or shrink claims

• The ATO requires that you must have the required records to claim car expenses for a car you own or lease.
• For logbook method, you must keep:
• A logbook covering at least 12 continuous weeks that represents your normal driving.
• Start and end odometer readings for the logbook period.
• For each journey: date, destination, purpose, odometer readings and kilometres, plus totals for business vs total kilometres.
• Receipts or evidence for car expenses (fuel, servicing, rego, insurance, repairs, finance interest, depreciation).
• NRMA notes that you must also keep all receipts relating to the vehicle, and a logbook must be renewed every five years.
• OracleAG explains that the logbook remains valid for up to five years if your usage pattern doesn’t change, and the ATO requires taxpayers to keep records for at least five years from when they’re used in a return.

Impact: How poor record-keeping reduces or kills deductions

• If you do not have a valid 12‑week logbook, the ATO can disallow the logbook method; you may be forced back to cents per km or only claim clearly substantiated actual costs, which:
• Immediately caps you at $4,400, even if your realistic logbook deduction would be $7,000–$10,000.
• If you do not retain receipts:
• You cannot substantiate many running costs (insurance, rego, repairs, interest), so your logbook deduction may shrink to just fuel estimates, often cutting it by 50% or more vs a fully substantiated claim.
• OracleAG stresses that the substantiation rules require evidence of both expenses incurred and the work-related nature of travel, and the ATO can reject claims without clear records.

Long-run cost of inaction (records):

• Using the earlier scenario (potential $9,000 logbook deduction vs $4,400 cents per km):
• Annual loss from failing to keep a logbook and receipts: roughly $4,600 in tax deductions.
• Over a 10‑year working period with similar usage:
• Total missed deductions: [ <mark class=“fig”>$4{,}600 \times 10 = <mark class=“fig”>$46{,}000 ]
• At a marginal tax rate of, say, 32.5%, that’s around $14,950 more tax paid over the decade due purely to poor record‑keeping (illustrative calculation based on ATO marginal rates, not explicitly stated in sources).

What this looks like in practice

Persona:

• Name: Jess
• Age: 34
• Job: Sales representative (employee)
• Income: $95,000 salary (mid‑career professional level; not a formal ATO threshold).
• Car: 4‑year‑old hatchback she owns outright
• Annual total car costs: about $11,000 (fuel, rego, insurance, servicing, tyres, depreciation — realistic combined cost, not an ATO benchmark).
• Work travel: ~16,000 km per year visiting clients, plus personal use
• Years to retirement: ~31 years (assuming age 65)
• Fund/account type: Individual employee, claiming work-related car expenses via her personal income tax return (ATO work‑related deduction rules).

Discovery 1 — Method choice:

• Jess currently claims using cents per km and has estimated 5,000 work km, giving her:
• Deduction: [ 5{,}000 \text{ km} \times <mark class=“fig”>$0.88 = <mark class=“fig”>$4{,}400 ]
• After keeping a 12‑week logbook, she discovers:
• Business‑use percentage is 70% of total kms.
• Logbook deduction would be: [ <mark class=“fig”>$11{,}000 \times 70% = <mark class=“fig”>$7{,}700 ]
• Extra deduction vs cents per km: $3,300 per year.

Discovery 2 — Km cap:

• Jess thought showing she drove 10,000+ work km would increase her cents per km claim, but she learns:
• Cents per km claims are capped at 5,000 km per financial year per car, even if she drives 15,000 work km.
• She realises that beyond 5,000 km, every extra work km earns $0 deduction under cents per km, while logbook can cover all kms via business-use percentage.

Discovery 3 — Records and logbook validity:

• Jess assumed she needed a new logbook every year, which felt too hard.
• She discovers:
• A valid 12‑week continuous logbook (with dates, odometer readings, journey details, and totals) is acceptable for up to five years if her usage pattern doesn’t change.
• ATO requires she keep the logbook and receipts for at least five years after using them in a return.
• This means a one‑off 12‑week effort can support up to five years of potentially higher deductions, worth:
• Up to $3,300 extra per year × 5 years ≈ $16,500 additional deductions over that logbook’s life in Jess’s scenario.

The full cost of doing nothing

Using Jess’s figures:

• Cents per km method (current behaviour):
• Annual deduction: $4,400 (5,000 km × $0.88).
• Logbook method with good records:
• Annual deduction: $7,700 (70% of $11,000 actual costs).

Annual difference from problems 1 and 2 combined (wrong method + poor records):

• $3,300 in missed deductions per year in Jess’s scenario.

Lifetime / career impact (modelling assumptions):

• Assume:
• Jess maintains similar work‑related car use and costs over 20 working years (not all 31, allowing for career changes).
• She continues to use cents per km and never keeps a logbook or full receipts.
• Total missed deductions over 20 years: [ <mark class=“fig”>$3{,}300 \times 20 = <mark class=“fig”>$66{,}000 ]
• At an illustrative marginal tax rate of 32.5%, this equals about: [ <mark class=“fig”>$66{,}000 \times 32.5% \approx <mark class=“fig”>$21{,}450 ] in extra tax paid over her career purely due to not optimising her car claim and not keeping records (calculation based on ATO marginal rates, not explicitly in sources).

What to do about it

1. Choose the right method for THIS year

1. Action: Compare cents per km vs logbook for your car.
2. Tool/portal:

• ATO “Expenses for a car you own or lease” guidance and Motor vehicle expense calculation methods pages (via ATO website).
• Use your past year’s car costs from bank statements or budgeting apps.

3. Steps:

• Gather last year’s total car costs (fuel, rego, insurance, servicing, repairs, interest, depreciation figure from purchase records).
• Estimate your business-use percentage (from any existing logbook, calendar, or mileage app). Multiply total car costs by that percentage to estimate a logbook-method deduction.
• Separately, total your work-related kilometres and multiply by $0.88, capped at 5,000 km, to estimate your cents per km deduction.

4. What “good” looks like:

• If logbook estimate > $4,400, the logbook method is likely better for you this year.
• Re‑check annually, as costs and usage can change.

2. Set up a compliant 12‑week logbook

1. Action: Start and complete a 12‑week continuous car logbook.
2. Tool/portal:

• ATO logbook rules on the car expenses page.
• Any mileage‑tracking app or paper logbook that records required details.

3. Steps:

• Pick a 12‑week period that reflects your normal work driving and note your odometer reading at the start.
• For every trip, record date, destination, purpose, starting and ending odometer readings, and kilometres, plus whether it’s work or private.
• At the end of 12 weeks, record the final odometer reading, total kms, total work kms, and calculate your business‑use percentage, then keep this logbook (paper or digital) with your tax records.

4. What “good” looks like:

• A logbook with no gaps in the 12‑week period, clearly showing work vs private trips, and summarising business‑use %, which you can apply to all eligible car expenses for up to five years if usage pattern stays similar.

3. Build a 5‑year record system for car costs

1. Action: Create a simple system to capture and store car expense evidence.
2. Tool/portal:

• ATO guidance on required records for car expenses.
• Your email/phone scanner app + cloud folder or physical file.

3. Steps:

• Make a dedicated folder (digital or physical) labelled “Car expenses – FY 2024–25” and repeat for each financial year.
• Each time you pay for fuel, rego, insurance, servicing, repairs, loan interest or buy the car, save the receipt, invoice or statement into that folder and note briefly if a cost is work‑related.
• At tax time, use these records to total your actual car costs for the year and keep them for at least five years after lodging your return, as required by the ATO.

4. What “good” looks like:

• Being able to show, for any claimed expense, who was paid, how much, what for, and when, plus supporting logbook/business‑use percentage, for at least five years from the relevant tax return.

A myth worth clearing up

Myth: “If I use the cents per kilometre method, I don’t need any records at all — I can just estimate the kilometres.”

Fact: While the cents per km method does not require a formal logbook, the ATO still requires you to “have the required records” and be able to demonstrate how you calculated your work‑related kilometres, such as through a work diary, schedules or patterns. Community tax guidance also emphasises that, in case of an audit, you must provide evidence of how you calculated the 5,000 km, like maintaining a work diary.

Sources

• https://www.ato.gov.au/businesses-and-organisations/income-deductions-and-concessions/income-and-deductions-for-business/deductions/deductions-for-motor-vehicle-expenses/motor-vehicle-expense-calculation-methods
• https://www.ato.gov.au/individuals-and-families/income-deductions-offsets-and-records/deductions-you-can-claim/work-related-deductions/cars-transport-and-travel/motor-vehicle-and-car-expenses/expenses-for-a-car-you-own-or-lease

Researched 2026-06-27.

Corrections & disclosure: an AI-assisted, human-reviewed guide. Every figure is dated and sourced above. Spot something out of date or wrong? Tell us and we’ll correct it — corrections are noted here and in the video description.