FAQ
Luxembourg - Tax Return

The deadline for filing the tax return for the previous calendar year is 31st of December. The deadline for the year 2023 is 31st of December, 2024.

You can claim your tax refund from Luxembourg up to 1 year back.

In 2024, you can only file a tax return / claim a refund for the tax year 2023.

Late filing of your tax return can result in a penalty in the form of a 10% tax increase. In addition, you can be fined between €25 and €250.

Failure to file a tax return may result in automatic taxation based on an estimate of your income.

No, you must file a tax return in addition to paying the fine.

To file the tax return you will need these documents:

• a confirmation of taxable incomes (Certificat de salaire) from each employer,
• EWR, which documents local income from your home country,
• ID card / passport,
• marriage certificate or birth certificate of the child, if any.

The Certificat de salaire is a form that every employer must give to their employees at the end of the year. It is a certificate of the employee's annual income and the taxes withheld from each month's wages for the previous calendar year.

The tax office will process the tax return and then pay the overpayment. The whole process takes on average 2 ‑ 12 months from the time the tax return is filed.

Yes, spouses can file a joint tax return and get a possible higher refund. This is only worthwhile if the spouse's net income is less than €13 000.

After filing your tax return, the tax office will send you a tax assessment stating the amount of tax and the due date.

Individuals in Luxembourg are assigned a tax class. There are 3 tax classes:

• Class 1 for single persons,
• Class 1a for single persons with a child and for single persons who have reached the age of 65 till the 1st of January,
• Class 2 for married persons and persons in a registered partnership (subject to certain conditions).

Married persons who are non‑resident and does not live separetely are in Class 1. If certain conditions are met, they can apply to benefit as tax residents and be placed in Class 2 (generally the tax class for residents and unseperated married couples). In this case, they must then file a joint tax return.

Identification number / file number (Numéro de dossier or Matricule) is an 11‑digit number, which is issued to Luxembourg taxpayers. The number is included in the letters you will receive from the Luxembourg tax office when you have to file your tax return. Keep this number carefully as you will need it to file your tax return.

The obligation to file a return in Luxembourg depends on several factors. In certain cases, you are obliged to file a tax return, for example if you have income from more than one job or if you run a business in Luxembourg.

There are also specific situations where filing voluntarily may be worthwhile, for example, to obtain tax overpayment thanks to tax credits and deductions.