For SA residents: "Gross income" is the total amount of worldwide (local and foreign) income that you earned during the tax year, excluding income that is of a capital nature. (Income of capital nature is money earned from selling your possessions, e.g. sale of your house).
Please note that "income" also includes money that is owed to you for work you performed, even if not paid to you yet - for example, you performed a service last month, but will only be paid next month.
Non SA resident: "Gross income" is the same as above, but limited to income from South African sources only.
Please also see the following related definitions: Income and taxable income.
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