Section 103:

Income Tax Act · PART VIII: RETURNS, COLLECTION AND PAYMENT OF TAX

consolidated text (as at 2017, amended since). juris shows the text as it was consolidated; it does not confirm that this is the law in force today.

103. Tax withheld deemed to be tax paid by employee Any amount withheld as tax under this Sub-part shall be deemed to be— (a) received by the employee at the time it was withheld; and (b) paid by him, and shall be credited against the income tax liability of the employee for the income year in which the emoluments were paid.

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Questions this section answers

Does the tax withheld from my pay count as tax I've already paid myself?