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# When should I complete Form 100?

###### You must complete form 100 when :
###### 
the household's taxable income exceeds €100,000 per year
in the event of multiple remunerations when taxable income exceeds €36,000 for taxpayers in tax classes 1 and 2 and €30,000 for taxpayers in tax class 1a.
for Luxembourg non-residents, when you are taxed at a flat rate.

Or if your taxable income in Luxembourg is not subject to withholding tax, such as for :

* income from the exercise of a liberal profession
* income from the rental of real estate
* income from salaries paid by a foreign employer or pensions paid by foreign pension funds
* taxable income comprising more than 1. 500 of net income from securities subject to withholding tax
* taxable income comprising more than €1,500 of directors' fees
* spouses who are not separated, one of whom is a resident taxpayer and the other a non-resident, who have opted for joint taxation and who have provisionally obtained tax class 2 on their withholding tax form.

If you do not meet any of the above conditions and the tax authorities have not expressly asked you to submit form 100, choose form 163.