@sheep - based on my understanding, "No Tax Free Threshold" means you do not want to claim the tax-free threshold on this job, and incorporate that in the calculation of witholding tax monthly..
a) example, you have job A, and Job B, you only claim the tax-free threshold to Job A.
b) if you have only one job, then you need to claim the tax-free threshold on that job/employer
When you/or your employer filled-up the Tax File number application form, did you tick that box " 'Do you wish to claim the tax-free threshold from this payer?'
<u></u><b>if you did. Means YES</b>, you want to claim the tax-free threshold, then your witholding tax every month will be calculated by your employer taking into consideration yung threshold (6k or 18kaud tax-free, whatever the law is)
<u></u><b>if not, This means, NO,</b> then you are not declaring that you want the tax-free threshold to be considered in the calculation of the witholding tax every month...
In short, mas malaking ang witholding tax monthly pag NO, compared sa YES.
BUT, in the end of the tax year, babalik sayo ang sobrang witholding tax... And calculation will still be based on taxing the money you earned after deducting the tax-free threshold (whether 6k or 18k aud)
malinaw ba? hahaha... hope this helps..