Under the self-assessment system, your income tax return is generally accepted at face value without adjustment. Even though you may receive a notice of assessment, which creates the formal obligation to pay tax, your return may be subject to further review or verification.
If a review shows any inaccuracies in income, deductions or entitlements, the Australian Taxation Office (ATO) may amend your assessment within a prescribed period. This period is called the period of review and commences when the Commissioner of Taxation gives you notice of your assessment.
The standard period in which the commissioner can amend an assessment for an individual or small business taxpayer is two years from the date that notice of assessment is given. This period can be extended to four years.
If fraud or evasion is suspected there is no time limit. The standard periods do not match the period for which taxpayers must keep records. This remains at five years from assessment.
Interest and dividends should always be declared. The ATO now obtains computer lists of all significant amounts received by way of interest and dividends from banks, building societies and public companies, which it may use to check the individual returns. Although a failure to declare dividends or interest payments may not be discovered for many years, a hefty fine will follow any discovery.
Tax at the highest marginal rate will be deducted automatically from interest payments unless a tax file number is supplied to the financial institution administering the interest bearing account.
Every taxpayer who carries on business must keep adequate records in English.