Filing your tax return

Which form to file as an independent, what to attach, and when.

Which form, and what to attach

Form 100 (income tax return)

The return you file as a self-employed person. Your business profit goes here.

Self-employed expenses annex

Declare your profit and expenses, with copies of your invoices attached.

Form 163 (annual statement)

For simpler situations without business income. You file form 100 or 163, never both.

Deductibles

Your CCSS contributions and business expenses lower your taxable profit.

The records you keep in the Document tracker are exactly what you attach - invoices, receipts and statements.

Deadline and how to file

File by 31 December of the year after the tax year, so the 2025 return is due 31 December 2026. You can file on MyGuichet with a LuxTrust certificate or on paper.

Orientation only. taxx.lu and the Luxembourg Inland Revenue (ACD) are the authority on your filing, and the ACD sets the forms and deadlines, which can change.