Commonwealth Consolidated Acts Commonwealth Consolidated Acts(1) You must retain the log book:
(a) first, until the end of the latest income year for which you rely on the log book to support your calculation of the * business use percentage for the * car; and
(b) then for another 5 years.
The period for which you must retain the log book is called the retention period .
(2) The 5 years start on the due day for lodging your * income tax return for that latest income year. If you lodge your return later, the 5 years start on the day you lodge it.
(3) However, the * retention period is extended if, when the 5 years end, you are involved in a dispute with the Commissioner that relates to a deduction worked out using a * business use percentage that you are relying on the log book to support. See section 900 - 170.
(4) If you do not retain the log book for the * retention period, you cannot deduct any amount worked out using a * business use percentage that you are relying on the log book to support. If you have already deducted such an amount, your assessment may be amended to disallow the deduction.
(5) For the purposes of the rules about retaining and producing records of expenses (see Subdivision 900 - G), the log book is treated as a record of the * car expenses for each year for which you use a * business use percentage that you are relying on the log book to support.
(6) If you lose the log book, there are rules that might help you in section 900 - 205. For the purposes of the rules about relief from the effects of failing to substantiate (see Subdivision 900 - H), not doing something required by this Division is treated in the same way as not doing something necessary to follow the rules in Division 900.