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# What are the penalties for late filing of your tax return?

If your declaration **is compulsory** and you send it to the Luxembourg Tax Administration (ACD) after the deadline (31st December), you risk a fine of up to €25,000. 
 
If your tax return **is not compulsory **and you file it after the deadline, then the refund to which you are entitled may be refused and your return will certainly not be processed by the tax authorities.

||| Please note: Only the receipt of your tax return by the ACD is considered valid. The postmark date is not accepted as proof of timely submission.