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# Can we file a joint tax return if one partner is a European civil servant and the other works in Luxembourg?

The possibility of filing a **joint tax return** in Luxembourg depends on the **type of union** (marriage or PACS) and especially on the **tax residence** of the partners, notably if one of them is employed by a European institution.

||| Important: **tax residence** is a **legal status for tax purposes**, which does not necessarily correspond to the physical place of residence.
||| Example: an employee of an EU institution may live in Luxembourg but have their tax residence in another country.

### **Income of European Union officials and staff**

* The salary of EU officials and staff is exempt from Luxembourg tax, upon presentation of a certificate from the European institution.
* However, their other income (rental income, investment income, etc.) may be taxable depending on their tax status (resident or non-resident).

### **Married couples**

Joint taxation always possible: a married couple can request joint taxation even if the European official is not a Luxembourg tax resident.

In this case, article **3, letter d) L.I.R**. must be ticked on the tax return, provided that the legal criteria are met:

* that at least 90% of the household's professional income is earned during the tax year by the taxpayer resident in Luxembourg.
* The European employee’s salary remains exempt, and the couple can benefit from joint deductions (mortgage interest, insurance premiums, etc.).

||| Income exempt from the EU salary is not taken into account when verifying the 90% household income threshold. 

### **PACS couples**

For PACS partners, joint taxation is only possible if both partners are Luxembourg tax residents.

Attention: tax residence is not the same as physical residence.
Example: one partner may live in Luxembourg but have their tax residence in another country.

Consequence: for PACS couples, eligibility for joint taxation strictly depends on tax residence status, not on where the couple lives.
If the European official is not a Luxembourg tax resident, the PACS does not entitle them to joint taxation. In this case, only the partner taxable in Luxembourg files an individual tax return.

### **Determination of the tax residence of a European official**

1. Arrival in Luxembourg solely to work in a European institution
* Tax residence remains in principle in the country of origin, even if the couple physically lives in Luxembourg.

2. Residence in Luxembourg for other reasons (before or alongside European employment)
* Tax residence is in principle considered Luxembourgish.

Joint taxation is then possible:
* For married couples, according to the classic rules,
* For PACS couples, provided that the PACS existed for the entire year and the partners lived together in Luxembourg.