AVZ chart, page-8985

Tysons,
The former provisional tax, is now known as Quarterly Incone Tax instalments and is determined and based on your last lodged income tax return at that time.
Generally calculated based on business, interest and dividend income (less estimated franking credits). It should be noted that ATO excludes Capital Gains when calculating tax instalments payable, on the basis that they are no regular and expected to reoccur every year (except for superannuation fund tax instalment calculations).
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