From 1 July 2017, if you are selling a home worth $750,000 or more, and you are a foreign resident, then the buyer must withhold 12.5% and pay this amount to the ATO. To avoid this requirement, Australian residents will need to obtain a clearance certificate.
A following recent REIQ release sets out the details: http://www.reiq.com/REIQ/Posts/REIQ_Update/New_withholding_tax_rules.aspx.
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