Cross-border workers: tax advice and tax returns in Luxembourg

Support tailored to your situation

The firm supports employees, pensioners and other taxpayers resident in Belgium or France whose situation has a tax connection with Luxembourg.

First tax return, annual follow-up, a change in your family or professional situation, a specific question: the work starts from the facts of your own case in order to identify your obligations and review the options open to you.

The key factors in your taxation

Your filing obligations

Tax withheld from your salary or pension does not necessarily exempt you from filing a tax return in Luxembourg. The firm checks your obligations and, where filing is not mandatory, considers whether voluntary filing would be worthwhile and which procedure is appropriate.

Tax assimilation

Tax assimilation (being taxed as a resident) allows you, subject to conditions and upon request, to benefit from tax provisions applicable to resident taxpayers. It does not change your country of residence.

The firm reviews your eligibility and the consequences of this option, taking into account your Luxembourg and foreign income, the deductions available and your family situation. For residents of Belgium, the specific provisions of the Belgium–Luxembourg tax treaty are also reviewed.

Your relationship and your children

Marriage, registered partnership, PACS or legal cohabitation: the taxation options must be assessed according to your status and the applicable conditions. The analysis covers, in particular, the arrangements for joint or individual taxation and the income of the spouse or partner to be taken into account.

Separation, divorce, shared residence (alternating custody) or contributing to the expenses of a child living in another household may also require specific review.

Your property and your foreign income

In the case of assimilation, foreign income is taken into account in determining the rate applicable to income taxable in Luxembourg. This does not mean that the foreign income itself is taxed there.

For a property let in Belgium or France, the income to be used in this calculation is determined according to Luxembourg tax rules. It therefore does not necessarily correspond to the amount shown on the tax return of the country where the property is located.

The firm also reviews the treatment of loan interest relating to your main residence, in light of the applicable conditions.

Remote working and days worked outside Luxembourg

Remote working, business travel and assignments abroad may change the allocation of taxing rights over your salary. The review takes into account the actual places of work, the number of days concerned and the provisions of the applicable tax treaty.

This tax analysis is separate from the analysis of the social security affiliation rules.

From analysis to your Luxembourg tax return

Depending on the agreed engagement, support includes reviewing your income and supporting documents, examining the relevant deductions and options, and preparing Form 100 and its schedules.

The treatments adopted and their consequences are explained to you. Where filing is part of the engagement, the return is submitted to you for approval before it is sent.

A targeted consultation, a second opinion or a comparative simulation may also be provided as a separate service. An in-depth study or several simulations are not automatically included in the preparation of a tax return.

A clear scope between Luxembourg and your country of residence

This support covers your Luxembourg taxation and takes into account the tax treaties applicable to your situation.

A tax return filed in Luxembourg does not replace your filing obligations in Belgium or France. Preparing your Luxembourg tax return does not include preparing the return for your country of residence, unless expressly agreed as a separate engagement.

The work covered, the documents required and the fees are specified before work begins.