Generally, Australian residents pay Australian income tax on all discounts received under an employee share scheme regardless of whether they are received in relation to employment in or outside Australia.
However, this rule may be affected by Australia's double tax agreements and the temporary resident rules.
If you are a foreign resident taxpayer, you only pay Australian income tax on discounts you receive under an employee share scheme to the extent that the discount relates to employment in Australia.
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Your residency for tax purposes and your country of employment can affect how you are taxed.