How do I send my tax return in Luxembourg Tax Authority ?

You must send either form 100 OR form 163, not both!

Which form should I send between 100 and 163?

Form 100 :

Two possibilities:

1) Submit the form and attachments on MyGuichet.lu.
Log in to your myguichet.lu account and submit your tax return and attachments.

How do I transfer my tax return to myguichet.lu? (ONLY form 100)

2) Send the form and enclosures by post to your tax office.
Print the PDF and sign the last page after checking the data. The address of the tax office is on the first page, top left.

Form 163 :

Only one option:

Send the form and attachments by post to your RTS office.
Print out the PDF and sign on the last page after checking the data. The address of the RTS office is on the first page, top left.

Updated on: 24/07/2024