If a tax return has been issued to you, there is a filing date on the return. The tax return needs to have been completed and returned before that time. What happens if you do not meet this deadline?
The first time you receive a EUR 226 fine for late filing. Does it happen again, then the fine is EUR 984. If it happens again, the fine goes up again to an amount of EUR 4.920 max. The tax office is rather rigged with this penalty. If too late, you have the penalty. If you appeal against the penalty then basically you have to state you were not too late and that is difficult if you look at the time line and you missed the deadline. However, if you missed the deadline because the wrong address details were used, you might have a chance.
The charging of the penalties is a good source of income for the tax office, we suggest not to make the source of income any better and file in time.