Country guide · Australia

An Australian log book is twelve continuous weeks, valid five years, and every entry must be in English

Two methods, and only one of them needs records

Cents per kilometre. 91 cents from 1 July 2026, for the first 5 000 business kilometres per car — and the excess is discarded rather than paid at a lower rate: s 28-25(2), "you must discard the kilometres in excess of 5,000." What it needs by way of substantiation is nothing. s 28-35, entire: "To use this method, you do not need to substantiate the car expenses for the car." You do need a way of showing how the kilometres were worked out, and the ATO names an automatic tracker as acceptable for that.

The logbook method. Everything below.

The Division applies to an individual, and to a partnership that includes at least one individual; "It does not apply to any other entity" (s 28-10). A sole trader and an employee use the same rate on identical terms.

What the log book holds

A continuous period of at least twelve weeks, representative of the year's travel. Per s 28-125(2), for every work-related journey:

• The day the journey began and the day it ended
• The car's odometer readings at the start and end of the journey
• How many kilometres the car travelled on the journey
• Why the journey was made

And per s 28-125(4), for the period as a whole: when it begins and ends, the odometer at each end of it, the total kilometres for the period, the business kilometres, and (e) the business kilometres expressed as a percentage of the total — which is the number the deduction is actually computed from, and the one most often absent.

Each entry made at the end of the journey or as soon as possible afterwards.

Odometer readings every year, whether or not you keep a log book

Readings at 1 July and 30 June, to compute the year's business-use fraction. The log book gives the percentage; the annual readings give the total it applies to.

The odometer records document has its own list

s 28-140(3), three lines that three earlier readings of this Subdivision walked straight past:

• The car's make, model and registration number
• If the car has an internal combustion engine, its engine capacity in cubic centimetres

Every entry must be in English

s 28-125(5), the last subsection of How to keep a log book: "Each entry in the log book must be in English." It sits after the four subsections that say what an entry contains, and it binds all of them.

Which reaches further than headings. s 28-125(2)(a) makes the date part of the entry — "the day the journey began and the day it ended" — so a log book whose dates render as "10 settembre 2026" has entries that are not in English, however English the column titles are.

What stays yours is the free text: a journey's reason under s 28-125(2)(d) is written by you, and nothing should be translating it.

The twelve weeks may cross 30 June — and then the year is a choice

s 28-120(2): "The period may overlap the start or end of the income year, so long as it includes part of the year." And s 28-110's first step is to "identify an income year for which to keep a log book".

So a window straddling 30 June is a valid log book for either of the two years it touches, and choosing moves the five-year validity by a whole year. It is a real decision, not a formality.

The neighbouring rule catches people with two cars: s 28-120(3) requires that "the log books for those cars must cover periods that are concurrent". Two windows in different months are not a valid pair.

Validity five years, retention longer, and they compose

Validity. A log book kept for one income year covers the next four (s 28-115(2)).

Retention. Distinct, and longer: s 28-150(1) — keep it until the end of the latest income year you rely on it for, "and then for another 5 years" — and those five start on the due day for lodging that year's return, or the day you actually lodge if later (s 28-150(2)). It is the only retention clock of the twenty-one countries here that starts at lodgment. Odometer records ride the same period, and an unresolved objection extends it indefinitely.

The two compose. A log book written for 2026-27 and relied on through its full validity must be kept about five years past the 2030-31 return — roughly ten years after it was written.

The sanction is the loss of the deduction (s 28-150(4)), not the administrative penalty: TAA 1953 Sch 1 s 288-25(2)(b) expressly carves out documents required under Division 900.

Why an app rather than a notebook

Nothing above requires software, and for twelve weeks a notebook is a perfectly reasonable instrument. What software changes is which entries survive twelve continuous weeks without a hole, and which arithmetic gets done.

What goes missing is never the distance. It is the odometer reading at the start of a journey on the fourth Tuesday, the reason for one visit among ninety, and the business percentage — because that is a division nobody performs until the return is due and the period has closed.

DriveHub records each drive in the background with the odometer at each end and asks afterwards which were work. "Year" means 1 July to 30 June for an Australian, on the report and on the review screen, and the twelve-week window is a period preset rather than something to count out on a calendar. Where the window straddles 30 June it asks which income year you are keeping the book for, because that is s 28-110's first step and nothing else can answer it. The report prints the period's totals and the business percentage, and the car's make, model, registration and engine capacity in cubic centimetres.

It is written in English for Australia whatever your phone is set to — in en-AU, so the dates read the way an assessor expects rather than in the phone's language under English headings.

This page states what Division 28 itself says, and cites the section so you can check. It is not tax advice. It can't account for your circumstances. Where money is involved, ask your tax agent — and bring the log book.