What do I have to send to the Luxembourg tax authority?

If you are required to file a tax return (or an annual statement) or have an interest in doing so, you must submit the forms generated by myTax to the Luxembourg tax authority, namely:

Furthermore, you also need to provide the Luxembourg tax authority with the certificates that allowed you to complete your declaration.

In the event that you do not send your certificates/supporting documents, your tax office may ask you, by postal mail or e-mail, to submit them for verification.