Extension of deadline for submitting income tax returns

An extension of the deadline does not have to be requested in this case. The tax return can still be submitted. If the return is submitted electronically, you will even be explicitly asked whether you wish to submit additional documents; you will then be asked to tick the appropriate box. If the tax return is submitted in paper form, this option does not exist. In this case, an informal notice must be attached to the return.

In the interest of both parties, the missing documents should be submitted as soon as possible.

Not in every case. However, the tax office will contact you if any documents or information are still required for processing the tax return.

Yes, if the announced documents are not absolutely necessary from the point of view of the tax office.