Australian tax returns for Individuals are due 31 …

Australian tax returns for Individuals are due 31 October 2013. Avoid penalties for late submissions by registering your details with a tax agent before 31 October. Assuming you are up to date with previous tax years, extensions to 15 May 2014 are available for most individuals.

http://www.ato.gov.au/Individuals/Lodging-your-tax-return/When-to-lodge-your-tax-return/

When to lodge your tax return | Australian Taxation Office

ato.gov.au

Tax returns cover the financial year, not the calendar year. The financial year begins on 1 July and ends on 30 June the following year. After the financial year ends, you have until 31 October to lodge your return (unless you use a tax agent).