Information for Residents

The Law of 4 December 1967 on income tax, as amended, lays down the applicable taxation limits for the purposes of determining the scope of taxpayers covered by the obligation to file an income tax return.

The table below contains a summary of various cases in which resident taxpayers are covered by this obligation:   

*T.I. = Taxable income in EUR

**If, in addition to income liable to withholding tax, the taxpayer is in receipt of net income exceeding 600 euros which is not liable to withholding tax, an income tax return must be completed, regardless of the amount of his/her taxable income.

***“Incidental income not liable to withholding tax at source” includes business income, agriculture and forestry income, income from independent professional services, life annuities, income from rentals and leases (rents and/or farm rentals), miscellaneous net income and income coming from abroad.

Notwithstanding the points mentioned above, the taxpayer must file a form 100 if requested to do so by the ACD.

Taxpayers who are wage earners and who do not fulfil these conditions, but who wish nevertheless to deduct certain expenses, may either request an annual adjustment or apply to the competent RTS tax office for a deduction to be entered on their tax card.

For further information, click on the link Imposition par voie d'assiette (impôt sur le revenu) - A à Z - Administration des contributions directes - Luxembourg (public.lu)

Officials of the Administration des contributions directes (ACD) are there to answer any questions of a general nature relating to tax matters. Please note, however, that the ACD does not act as an independent tax adviser.

For questions relating to VAT, registration duties, death duties and transfer tax, please contact the Administration de l’enregistrement, des domaines et de la TVA (Registration Duties, Estates and VAT Authority) via the following link:

https://pfi.public.lu/fr/support/contact.html

As from the 2022 taxation year, natural persons who are subject to assessment (that is to say, required to file an income tax return) are obliged to file their income tax return for the taxation year N (form 100), together with their business tax return for the taxation year N, by no later than 31 December in taxation year N+1.

If the deadline for filing the income tax return is not met, this will give rise to the imposition of a surtax for late filing or non-filing, or a pecuniary penalty, or both those sanctions. As regards taxpayers who are not covered by the assessment obligation, any income tax return filed after 31 December in year N+1 is not taken into account by the Administration des contributions directes.

The deadline for filing the income tax return may not be extended beyond 31 December.

The income tax return can be filed with the competent tax office

• in paper format;
• online via MyGuichet, using a LuxTrust product:
  • either in a downloadable PDF format; or
  • by way of an automatic process

The forms in question can be accessed by clicking on the following link:

https://impotsdirects.public.lu/fr/formulaires.html

Outside office hours, letter boxes are available in front of the Administration’s premises for use by taxpayers wishing to deposit their tax returns in a sealed envelope.

The key date for determining whether or not a child forms part of his/her parents’ household for tax purposes is 1 January in the taxation year concerned (save for children born during the course of the year, who automatically form part of their parents’ household). Also excepted are children who themselves have one or more dependent children, as well as married children. Such children are deemed to constitute a household jointly with their own child or children or with their spouse, and can therefore no longer form part of the parents’ household for tax purposes.

Children aged 21 or over on 1 January in the taxation year, living under the same roof:

who are in receipt of

• the family allowance; or
• State financial aid for higher education; or
• volunteer support

and who

• are pursuing, on a continuous basis, a full-time course of post-secondary studies extending over more than one year as at 1 January in the taxation year,
  • belong to their parents’ household for tax purposes, even if they start working during the course of that same taxation year.

Children aged under 21 on 1 January in the taxation year, living under the same roof:

• automatically form part of their parents’ household, regardless of their status (student or wage earner), provided they are living under the same roof or temporarily elsewhere for a reason other than carrying on a gainful activity,

apart from children who themselves have one or more dependent children. Such children are deemed to constitute a household jointly with their own child or children, and can therefore no longer form part of the parents’ household for tax purposes.

The taxpayer’s tax liability arises from the time when he or she realises the income triggering that liability.

Consequently, the filing of an income tax return remains obligatory for the taxation year in which the widowed parent dies, if the conditions giving rise to that obligation are met.

The tax claim arises prior to the issue of the notice of assessment, or in the event of any modification triggering that claim.

The statutory heirs, apart from those who have officially waived their inheritance (the formalities for such waiver are to be carried out via a notary), are liable for the tax payable, or alternatively qualify for any tax refund payable, on behalf of the widowed deceased.

Since your spouse was still alive on 1 January of the last taxation year (year N), you still fall within the scope of joint assessment for that year.

With effect from the taxation year following the year of death (year N+1), you are required to complete an income tax return in your own name if you fulfil any of the criteria listed under the heading “When is a taxpayer obliged to file an income tax return (form 100)?”

The following table shows the difference, in terms of tax class, between the situation of resident taxpayers who are married and those living in a partnership:

(*): whose household includes one or more children entitled to a tax abatement

(**) : the transitional period applies in respect of persons who are divorced, judicially separated or living apart pursuant to a legal exemption or an order of a judicial authority, as well as widows/widowers who are, in principle, classed in tax class 2 during the year in which the event (judicial decree of separation or divorce) took place and the ensuing three years, if, before that time and for a period of five years, they did not avail themselves of this provision or a similar previous provision.

Married couples who are resident in Luxembourg are automatically classed in tax class 2 on their tax card, and are automatically assessed jointly as a couple (unless they jointly opt to be taxed individually).

Since the amount of tax withheld in accordance with the schedule of income tax on wages is less in tax class 2 than in tax classes 1 or 1a, the monthly amount of tax withheld is less and the amount of take-home pay is higher.

However, married couples are required to file an income tax return (assessment) if they fulfil the conditions laid down (see point 1 of this section). Joint taxation subsequently aggregates the income of the household, and the progressivity of the income tax scale triggers a recalculation of the tax actually payable by the married couple for the taxation year in question.

By contrast, partnership does not alter the tax class on the taxpayer’s tax card. Partners may either continue to file their respective tax returns individually or opt, on joint application, to be assessed jointly, provided that:

• the partnership has existed throughout the entire taxation year, and
• the partners have shared a common domicile or residence throughout the entire taxation year in respect of which the application for joint assessment is made.

If all of these conditions are fulfilled, the competent tax office assigns tax class 2 for joint assessment. The final statement therefore takes into account, first, the total income tax in accordance with the tax rate applicable to tax class 2 and, second, the tax withheld during the year in question in accordance with the rate for tax class 1, 1a or 2.

Resident taxpayers subject to joint assessment are automatically classed in tax class 2. Consequently, their income is aggregated on the tax return. The resultant amount is reduced by the tax withheld at source on wages/salaries or pensions, foreign taxes chargeable and tax prepayments, so as to arrive at the balance of tax to be paid or refunded.

If married taxpayers opt, for example, for individual assessment without re-allocation of income (“pure” assessment), they are re-assigned to tax class 1.

For the persons who have opted for individual assessment with reallocation however, the tax class is not entered on the tax card of the resident taxpayer; instead, a taxation rate is entered on it. The latter corresponds to the rate which would be applicable to resident taxpayers classified in tax class 1 and taxable on both their local and foreign income.

In the case of so-called “pure” individual assessment, a married taxpayer is assessed, in principle, on the basis of the adjusted taxable income of that taxpayer alone. A joint and irrevocable application for individual taxation entails an assessment and thus the submission of an income tax return after the expiration of the taxation year to which the application relates.

You can access a simulator by clicking on this link:  https://impotsdirects.public.lu/fr/baremes/personnes-physiques.html

Where the household includes children (of one or both parents), it is necessary, first of all, to determine the (maximum) ceiling for the deductible expenses to be taken into account.

In the case of “pure” individual assessment, that ceiling is divided by 2 and each of the taxpayers can increase his/her personal ceiling by one half of the total ceiling brought about by the existence of the children.

Example in relation to special expenses:

In the case of individual assessment with re-allocation of income, the breakdown of adjusted taxable income depends on the distribution key chosen by the taxpayers, which may be, for example, 75/25 or 60/40. Where there is no indication of the distribution key that the taxpayers wish to opt for, the tax office will apply a 50/50 split.

In order to determine which model is most favourable to him/her, the taxpayer may seek advice from an independent tax consultant or rely on a simulation via the website guichet.lu, by clicking on this link:

https://guichet.public.lu/fr/citoyens/fiscalite/declaration-impot-decompte/activite-professionnelle/fiche-retenue-impot/imposition-collective-individuelle.html

Expenses relating to children’s university studies are not deductible. The Law on income tax provides that such expenses are covered:

• either by the tax abatement granted where the child forms part of the taxpayer’s household; or
• by an allowance for extraordinary expenses known as the “taxable income allowance for dependent children not forming part of the taxpayer’s household”, where the child does not form part of the taxpayer’s household.

The tax abatements for children are credited either in the form of:

• family allowances paid via the “Zukunftskeess”, i.e. the Children's Future Fund (Caisse pour l'avenir des enfants - CAE); or
• State financial aid (by way of grants) for higher education, paid by the Centre de documentation et d'information sur l'enseignement supérieur (CEDIES, Higher Education Documentation and Information Centre); or
• volunteer support pursuant to the Law of 31 October 2007 on voluntary service by young persons, as amended, paid by the Service national de la jeunesse (SNJ, National Youth Service).

The CIS (tax credit for wage earners) and the CIP (tax credit for pensioners) feature only on, respectively, the “certificat de salaire, de retenue d’impôt et de crédits d’impôt bonifiés” (certificate in respect of salary, withholding tax and tax credits) (drawn up by the employer), and the “certificat de pension ou de rente, de retenue d’impôt et de crédits d’impôt bonifiés” (certificate in respect of pension or annuity, withholding tax and tax credits) (drawn up by the pension fund), and do not have to be shown on the income tax return. The competent tax office reserves the right where necessary to recalculate the amount of tax credit previously granted where more than one tax card has been drawn up simultaneously in respect of one and the same taxpayer (e.g. where there has been more than one employer for the same period of employment during the taxation year).

Further information in respect of the CIS can be found via the link https://impotsdirects.public.lu/fr/az/c/credit-impot-salaries.html and in respect of the CIP via the link https://impotsdirects.public.lu/fr/az/c/CIP.html.

The only supporting documents needing to be attached when filing the income tax return of a natural person are:

• the annual remuneration certificate and/or pension certificate;
• the bank certificate relating to a mortgage loan taken out during the course of the taxation year concerned, stating the balance of the loan at the end of the taxation year and the amount of debit interest, as well as any interest subsidies and rebates by way of housing assistance;
• the declaration of partnership at the time of the first year of joint assessment;
• the mandate agreement (form 101) (required only for returns established and transmitted entirely digitally).

The various ACD annexes must be attached, depending on the taxpayer’s tax situation. The ACD reserves the right to call for additional supporting documentation within the framework of its investigative remit. Supporting documents bind only the person filing the return.

To add a supplementary document to the income tax return before the assessment has taken place, the taxpayer has three options: he/she can either send it by post or via the contact form, or deliver it in person to an official in the natural persons tax office dealing with the file.

The address of a given tax office can be found by clicking on the link  Compétences et adresses - Profil de l'Administration - Administration des contributions directes - Luxembourg (public.lu)

You can find out the office hours (opening and closing times) of the tax offices by clicking on the link https://impotsdirects.public.lu/fr/az/h/heures.html

For information regarding a rectification following the issue of a notice of assessment, please refer to the question “What is the procedure for requesting a revision of a recently received notice of assessment?” under the heading “Applying for a revision/protest”.

If you have any questions concerning the notice of assessment, you can either fill in the contact form appearing on the website of the Administration des contributions directes or contact your natural persons tax office directly by telephone, e-mail or post.

To find the address of the RTS non-residents office, please click on the following link: Compétences et adresses - Profil de l'Administration - Administration des contributions directes - Luxembourg (public.lu)

In the event that the income of the household changes significantly (e.g. reduction in working time, change of status from wage earner to pensioner, loss of employment, etc.), you can  apply for the tax prepayments to be redetermined. You must send a written application, containing a duly substantiated statement of reasons, to the competent tax office, either by post or via the contact form appearing on the ACD’s website. Please ensure in this connection that you enclose all the documents needed for a proper evaluation of the income currently available to your household.

If you change your address during the course of a given year, the competent tax office is determined by reference to the address at which you officially resided at the end of the taxation year in question. The file is sent internally from the old tax office to the new one, so no action on your part is required and there is nothing that you need to do.

If you need information concerning your tax card, you can either fill in the contact form appearing on the website of the Administration des contributions directes or contact the competent RTS office by telephone or e-mail.

To find the competent office, please click on the following link: Service d'imposition - Section RTS, retenue d'impôt sur les traitements et salaires - Profil de l'Administration - Administration des contributions directes - Luxembourg (public.lu)

In the event of a change of civil status, private address or employer, the tax card of a taxpayer who is affiliated to the Centre commun de la sécurité sociale (CCSS, Joint Social Security Centre) is automatically updated by the competent RTS office within a period of approximately 30 working days. The taxpayer does not need to do anything or submit any request.

On the other hand, the taxpayer needs to take steps in the event that the municipality in which he/she works changes, without there being any change of employer. The taxpayer should give notice of such change using form 164.

That form should also be used if the taxpayer discovers an error on his/her tax card.

It should further be noted that, since 1 January 2023, the annual tax cards (for resident and non-resident taxpayers) have been definitively replaced by multi-annual tax cards. These new tax cards remain valid until such time as a change occurs which requires them to be updated (change of address, new employer, change of tax class, tax abatements not automatically carried over from the previous taxation year). Consequently, the wage earner or pensioner is no longer automatically sent a tax card by post each year; this only happens when a new tax card is created on account of a change or changes to one or more entries.

As a taxpayer classed in tax class 1, you are automatically assessed at the rate of 33% in respect of all additional remuneration that you receive over and above your main income. Your primary remuneration is deemed to be that which is the most stable and the annual amount of which is expected to be the highest out of all your sources of income.

Set out below is a table summarising the rates applied on the additional cards:

Where no tax card exists, the employer or any other paying body (e.g. ADEM, CNS, CNAP, etc.) is required to determine the withholding tax on the basis of the highest tax rate for tax class 1, which cannot be lower than 33%.

In a tax household (assessed individually or jointly) having more than one tax card, the highest income (wage or pension) is taken as the primary tax card to be assessed in accordance with the scale of withholding tax on salaries and/or pensions.

The 15% rate is applied on the additional tax card. This is a flat rate that depends on your tax class.

Set out below is a table summarising the rates applied on the additional cards:

Automatic transcription is not possible, since the abatements in question are only granted in response to a duly completed application accompanied by supporting documentation (e.g. the single-parent tax credit, exceptional charges, alimony, etc.).

For the purposes of determining the withholding tax on salaries, certain tax-deductible expenses or tax credits may be taken into account, either automatically or upon application using form 164. Each tax deduction entered on the tax card as a tax abatement is taken into account in determining the tax withheld at source, irrespective of the applicable tax scale (annual, monthly or daily). Any abatement or rectification wrongly entered on the tax card may be automatically cancelled by the ACD.

The following entries may appear on the tax card:

• a deduction in respect of lump-sum travel expenses «FD»,
• a deduction in respect of professional expenses «FO»,
• a deduction in respect of lump-sum professional expenses «FFO»,
• a deduction in respect of special expenses «DS»,
• a deduction in respect of lump-sum special expenses «FDS»,
• a tax credit for wage earners «CIS»,
• a tax credit for pensioners «CIP»,
• an abatement for exceptional charges «CE» et
• a single-parent tax credit «CIM».

Since the taxation year 2021, two new deductions have appeared on the tax card of wage earners and/or pensioners:

• FFO: lump-sum professional expenses (540 €/300 €), and
• FDS: lump-sum special expenses (480 €).

These deductions are designed to bring deductions from remuneration that are carried out on a provisional basis during the course of the year more into line with the definitive tax fixed at the time of the assessment.

N.B. There is no need to apply for these deductions to be entered; they are automatically entered on the tax cards of those taxpayers who are entitled to them.

In certain cases, the rates of withholding tax may be reduced on application to the competent RTS office. In order to obtain a reduced rate, copies of the last three months’ salary certificates (of both spouses, where applicable) must be attached to the application for modification, marked “please reconsider my rate at the lowest”.

The withholding tax may be adjusted by the employer or the pension fund as from the new date of validity appearing on the updated tax card. Where a reduced rate is entered on the additional tax card, the amount of tax withheld will be automatically regularised by way of a special annual adjustment working in the wage earner’s favour or to his/her disadvantage.

For further information, click on the link Taux de retenue réduit - A à Z - Administration des contributions directes - Luxembourg (public.lu)

Provided their agreed gross hourly pay does not exceed twenty-five euros, temporary employees hired by a business are assessed to tax at a flat rate of 10%. In such cases, no tax card is created.

Following the end of the taxation year in question, a temporary employee assessed on a flat-rate basis may request that the assessment of the remuneration received be regularised, either by way of an annual adjustment or by way of assessment (that is to say, the filing of an income tax return), as the case may be.

Thus, this provision applies only to temporary employees performing assignment contracts concluded with temporary-work agencies.

The deadline for filing the annual adjustment for year N is 31 December in year N+1.

That deadline is an extinctive time-limit; it cannot be extended.

An annual adjustment filed after the deadline of 31 December in year N+1 will not be taken into account by the Administration des contributions directes.

With the exception of taxpayers who file an income tax return (form 100), any resident wage earner or pensioner is entitled, in principle,  to request a regularisation of withholding tax on the basis of an annual adjustment (form 163) for the purposes of deducting his or her special expenses, the most common of which are debit interest payments of any kind that are not economically related to the purchase of real estate (e.g. consumer loans, current account, credit cards, etc.), insurance (linked to the insured and not to the things insured), building saving contracts and exceptional charges.

The form, duly completed and signed, must be sent, together with the relevant supporting documents, to the competent RTS office for the region in which the taxpayer resides.

To find the competent RTS office, please click on the following link: Service d'imposition - Section RTS, retenue d'impôt sur les traitements et salaires - Profil de l'Administration - Administration des contributions directes - Luxembourg (public.lu)

For further information, click on the link Décompte annuel pour salariés - A à Z - Administration des contributions directes - Luxembourg (public.lu)

The CIS (tax credit for wage earners) and the CIP (tax credit for pensioners) are shown only on, respectively, the “certificat de salaire, de retenue d’impôt et de crédits d’impôt bonifiés” (certificate in respect of salary, withholding tax and tax credits) (drawn up by the employer) and the “certificat de pension ou de rente, de retenue d’impôt et de crédits d’impôt bonifiés” (certificate in respect of pension or annuity, withholding tax and tax credits) (drawn up by the pension fund), and do not need to be shown on the annual adjustment.

The competent RTS office reserves the right where necessary to recalculate the amount of tax credit previously granted where more than one additional tax cards has been drawn up in respect of one and the same taxpayer (e.g. where there are several consecutive employers over the course of the same taxation year).

Further information can be found via the link CIS (ou CIP) - A à Z - Administration des contributions directes - Luxembourg (public.lu)

The “certificat de salaire, de retenue d’impôt et de crédits d’impôt bonifiés” (certificate in respect of salary, withholding tax and tax credits) must be attached to the request. The ACD reserves the right to call for additional supporting documentation within the framework of its investigative remit.

Form 164 may be used to request the creation or rectification of, inclusion of an abatement on, or creation of a duplicate of, a tax card for the current taxation year for resident and non-resident wage earners and pensioners treated as residents (under certain conditions, a non-resident taxpayer may be treated as a resident taxpayer). Practical details in this regard can be found on the last page of form 164.

Form 163 (annual adjustment) may be used to request the regularisation of withholding tax deducted from the salaries and pensions of resident or non-resident taxpayers for the preceding taxation year.

Each taxpayer is assigned a tax class. The main distinctions drawn are between unmarried persons, single parents, married persons/persons in partnerships and widowed or divorced persons.

The table below contains a summary of the different tax classes applicable to resident taxpayers:

(1): For persons opting for individual assessment with re-allocation of income, the tax class is not shown on the resident taxpayer’s tax card; instead, a taxation rate is entered on it corresponding to the rate that would be applicable to resident taxpayers in tax class 1 who were taxable there on account of both their local and their foreign income (realised in Luxembourg and/or elsewhere).

Further information can be found via the link Revenus professionnels - A à Z - Administration des contributions directes - Luxembourg (public.lu)

(2): The tax class remains unchanged on the tax card, regardless of whether or not there is joint assessment

(3): the transitional period applies in respect of persons who are divorced, judicially separated or living apart pursuant to a legal exemption or an order of a judicial authority, as well as widows/widowers who are, in principle, classed in tax class 2 during the year in which the event (judicial decree of separation, divorce or death) took place and the ensuing three years, if, before that time and for a period of five years, they did not avail themselves of this provision or a similar previous provision.

From a tax point of view, unmarried persons living together form two distinct households, despite the fact that they are sharing a home.

Where the parents have more than one joint child, all of the joint children form part of the household of the parent in receipt of the first payment of the tax bonus for the oldest joint child. That parent is in principle classed in tax class 1a.

A child may not belong to more than one tax household during the course of a calendar year. If he/she moves from one parent’s household to that of the other, it is the parent in receipt of the first payment of the family allowance to which the existence of the child gives rise during the course of the taxation year concerned who retains the right to classification in tax class 1a for that year.  Where, on the other hand, the family allowance, financial aid for higher education or volunteer support is paid to the child, having attained his/her majority, that child is deemed to form part of the household of the taxpayer in which he/she is living at the start of the taxation year in question.

N.B. In the case of alternating custody, the tax office will accept the parents’ choice as to which household the child belongs to.

In the case of “simple” separation, i.e. separation otherwise than pursuant to a court order, the two spouses continue automatically to be jointly assessed, even if they reside at different addresses. Consequently, tax class 2 is not modified. It follows that the spouses are equally liable, jointly and severally, to pay any tax debts relating to a taxation year involving joint assessment.

Persons who are divorced, judicially separated or living apart pursuant to a legal exemption or an order of a judicial authority are, in principle, classed in tax class 2 during the year in which the event takes place and during the ensuing three years (transitional period).

Thus, during that transitional period, you are assessed individually, whilst remaining in tax class 2 on your tax card. After the transitional period, you are once again classed:

• either in tax class 1; or
• in tax class 1a if there are dependent children or if you are aged over 64 on 1 January of the taxation year concerned.

N.B. The transitional period may begin even before the divorce. Where an interim order, made prior to pronouncement of the effective decree of divorce, authorises the judicial separation of the spouses during the currency of the divorce proceedings, the year in which the interim order is made is the last year of joint assessment (year N) and the transitional period begins the following year (N+1), even if the divorce takes place during that same year (N+1).

The year during which one of the spouses dies is regarded as the last year of joint assessment (year N). The three taxation years thereafter constitute the “transitional period” during which the surviving spouse retains tax class 2 on his/her tax card. From the fourth year (year N+4) onwards, the surviving spouse is classed in tax class 1a (unless he/she remarries).

If the amount shown on the statement of account is preceded by the minus sign “-”, that is to say, a negative number/balance is involved, the taxpayer is entitled to a tax refund. If, on the other hand, the amount is not preceded by any sign, this means that a tax liability is still outstanding and payable. That amount is to be paid to the bank account of the Administration des contributions directes, stating the file reference number and the taxation year concerned.

Where there is an overpayment of tax prepayments over the course of year N, the excess is not in principle reimbursed; instead, it is offset against the amount found to be payable when the statement for taxation year N is drawn up.

You can find details of the bank accounts by clicking on the link Service de recette - Profil de l'Administration - Administration des contributions directes - Luxembourg (public.lu).

Any refundable excess will in principle be paid into your account within 5 to 10 working days following receipt of the statement of the assessment concerned, provided you have a Luxembourg bank account and provided your bank details are known and correct.

Payment of a tax refund into a foreign bank account may take a while longer (on average, up to three weeks).

Where a taxpayer receives a statement showing a balance that is due and payable, he/she may request extra time in which to settle his/her tax indebtedness. That request must be in writing and must be duly justified by a statement of reasons; it must also be accompanied by all relevant supporting documentation, and must be submitted to the competent tax office before the deadline for payment of the balance due (the date of actual receipt by the tax office counts as the decisive date in this regard).

An extension of time for payment does not constitute a right to which the taxpayer is entitled, but rather the grant of a favour. The official dealing with the request for an extension will assess whether or not it is justified. If it is approved, a letter containing details of the instalments to be paid will be sent automatically to the person making the request.

On the other hand, no extension of time will be granted where the taxpayer’s financial situation is such as to enable him/her to easily discharge his/her tax indebtedness or he/she has not yet paid his/her tax prepayments.

In the case of joint assessment, the spouses/partners are jointly and severally liable, on an unlimited basis, to pay any outstanding amounts of tax due. Consequently, each spouse/partner is required to pay the whole of the tax debt, and each spouse/partner may be pursued for the entirety of the debt in the event of enforced recovery. In other words, they must reach an amicable agreement for the purposes of discharging their tax indebtedness, failing which proceedings may be brought against them.

It is not possible to apportion the amount due in such a way as to reflect the shares respectively payable by each spouse individually.

Every due date must be respected. The expiry of a deadline for payment triggers an obligation to pay default interest at the rate of 0.6% per month on the amount of tax due.

A taxpayer seeking additional time for payment may submit a duly reasoned written request to the competent tax office, either by post or via the contact form. Such request must be lodged before the deadline for payment of the balance of tax due (the date of actual receipt by the tax office counts as the decisive date in this regard).

You should send an e-mail to the competent tax collector’s office, indicating your account number. Such request must, without fail, contain a statement of bank details (relevé d’identité bancaire - RIB) or a letter from your bank confirming that you are the holder of the bank account in question.

The fixing of tax amounts, prepayments and penalties falls within the remit of the tax offices. Please get in touch with the competent tax office, which will be happy to provide you with detailed information concerning the origin of the amounts outstanding and the way in which they have been determined.

Each payment made by you must precisely indicate, in the relevant communication, the type of tax and the taxation year to which your payment relates, failing which the tax collector’s office will allocate your payment in accordance with the allocation rules set out in §123 of the Loi générale des impôts (General Law on Taxes).

If you have any questions, please click on the following link to find the competent tax collector’s office: Service de recette - Profil de l'Administration - Administration des contributions directes - Luxembourg (public.lu).

The tax collector’s office has the right to offset, against any excess amount(s) in your favour, other amounts that are due from you. This may be done within one and the same tax file in order to offset surpluses against debit amounts, or indeed between different tax files (e.g. where the taxpayer has more than one tax file within the administration).

As a general rule, the tax office will send a letter to the taxpayer in order to notify the latter of the offsetting.

The fixing of default interest is provided for in the Tax Law, together with the way in which it is calculated. Consequently, the tax collector’s office is unable to cancel a legal requirement.

Default interest starts to run as from the first day of the month following that in which the tax debt became due, and is charged at the rate of 0.6% per month. The month in which payment is made counts as an entire month. It follows that, regardless of whether the payment takes place on the first or the last day of the month, the interest will be due for the whole of the month during which the payment is made.

Neither a protest nor a complaint affects the payability of the tax debt concerned. The recovery of that debt cannot be suspended, and in the event of non-payment, the tax collector’s office has the right to compel you to pay up by all legal means.

After lodging your protest with the Director of the Administration des contributions directes, you can submit a written application for a stay of enforcement to the tax office which issued the notice of assessment in question.

N.B. The grant of a stay of enforcement is not a vested right; in arriving at its decision, the tax office enjoys a discretionary power

Tax debts generally lapse and expire after five years (in certain cases, 10 years).

Waiver of limitation is an act whereby the taxpayer declares that he/she waives, vis-à-vis the Administration des contributions directes, any such limitation in time of his/her tax indebtedness.

Such a waiver of limitation must be registered before the limitation takes effect, thus before 31 December in the year in which the limitation period comes to fruition.

If you do not sign and return the document to the Administration des contributions directes, it will be obliged to interrupt the limitation period by some other means, i.e. by an order to pay or by an attachment of your account or your salary.

As far as the Administration des contributions directes is concerned, the identity of the person from whom the transfer of funds originates plays a subordinate role. The important thing is that a third-party payor should clearly state your tax file number in his/her bank transfer communication.

Prepayments are fixed by the tax office, which bases its calculation on the most recent assessment carried out or, in the absence of any previous tax return or assessment, on an estimate of your income.

Such prepayments fall due for payment on the dates indicated in the statement. Failure to make those prepayments gives rise to default interest and may result in enforced recovery measures on the part of the tax collector’s office.

If you consider that the prepayments fixed are too high, you should get in touch with the competent tax office, which may, where appropriate, carry out a recalculation.

However, as long as the prepayments are not reduced or cancelled, the tax collector’s office will proceed to collect them.

When a request is made for rectification of a recently issued notice of assessment, this is known as an “application for revision”.

A taxpayer wishing to apply for a revision of his/her notice of assessment, for example by reason of his/her having forgotten to include an important document when drawing up his/her tax return, may lodge an application for revision within three months following notification of the initial notice of assessment. Such an application must be sent by post to the competent tax office, accompanied by all relevant supporting documents; any corrective notice issued must likewise be notified within three months.

You can address your complaint:

• either to the relevant official in your tax office, who will pass it to the Director of the Administration des contributions directes, or
• directly to the Director of the Administration des contributions directes.

The Director of the Administration des contributions directes will be called upon to rule on the complaint.

It is recommended that you submit your complaint in writing.

Exceptionally, you may make your complaint orally to the relevant official in your tax office. In that event, the complaint will only be valid if it has been duly recorded in a signed written document.

A complaint made by fax will be accepted, but a complaint made by telephone or by e-mail will not be.

You may express yourself in one of the three official languages of the Grand Duchy of Luxembourg, namely Luxembourgish, French or German.

The Director’s decision on your complaint will be formulated, in principle, in the language of the application relating thereto.

In principle, it is the taxpayer contesting a decision of the tax office who has the right to submit a complaint to the Director of the Administration des contributions directes.

A third party may also be instructed to submit the complaint. In such a case, that third party acts as the representative and proxy of the person against whom the decision of the tax office has been issued.

That third party must hold an express, special mandate, that is to say, a written power of attorney clearly expressing the taxpayer’s intention to confer on the proxy power to act on his/her behalf by way of a complaint against the decision at issue.

In the case of representation by a lawyer, the latter automatically holds a mandate.

The Tax Law provides for various remedies against decisions of the Administration des contributions directes:

1. A protest against a notice of assessment or, as the case may be, another administrative decision must be addressed to the Director of the Administration des contributions directes within three months from the date of notification of the notice at issue.
2. A formal hierarchical appeal (“recours hiérarchique formel”) may be brought against a discretionary decision taken by the tax office (e.g. refusing to extend a deadline for payment, or fixing a surcharge). It must likewise be addressed to the Director of the Administration des contributions directes within three months from notification of the decision at issue.

Where the last day of the period is a Saturday, Sunday or statutory public holiday, that period is extended until the next working day. Once that period has expired, the complaint will be deemed to be out of time and thus inadmissible.

The complaint (protest or formal appeal to a higher administrative authority) must contain:

• the name and address of the complainant (i.e. the person lodging a protest or a formal hierarchical appeal against a severable act);
• the decision that you wish to contest, for example:
  “protest against the notice of assessment to income tax, dated 12 December 2002, for the year 2001”,
  “formal appeal to a higher administrative authority against the fixing of a surcharge for late filing amounting to 10% of the amount of tax fixed by the notice of assessment for the year 2001”.

The complaint must be submitted within three months from notification of the decision at issue.

Where the last day of the period is a Saturday, Sunday or statutory public holiday, that period is extended until the next working day.

Once that period has expired, the complaint will be deemed to be out of time and thus inadmissible.

It is recommended that you submit a separate complaint for each contested decision.

Example: you receive the 2022 and 2023 income tax assessment notices on the same day and you wish to lodge a complaint against both notices. Since there are two notices in all, thus two separate enforceable decisions, you should lodge two separate protests.

The Director of the Administration des contributions directes may either reject your complaint or declare it to be well founded (or partly well founded), or may annul the decision of the tax office.

The Director’s decision may be the subject of an appeal, to be lodged within three months from notification thereof before the Tribunal administratif (Administrative Court). An appeal against the judgment of the Tribunal administratif may be lodged before the Cour administrative (Higher Administrative Court) within 40 days after notification thereof.

In the absence of a decision by the Director within six months following the submission of the protest, the protest may be regarded as having been rejected, and you have the right to lodge an appeal before the Tribunal administratif against the initial tax decision (notice of assessment). 

However, following the expiry of that six-month period, the matter does not necessarily have to be brought before the Tribunal administratif, and the Director’s decision may still be issued after that period has expired.

In the event that, more than six months after lodging your protest, you have still not obtained any decision on the part of the Director, you may:

• either wait to receive the Director’s decision concerning your protest; or
• lodge an appeal against the decision forming the subject-matter of the protest, before the Tribunal administratif, 1, rue du Fort Thuengen, L-1499 Luxembourg. The application instituting the appeal proceedings must contain the appellant’s surname(s), first name(s) and domicile, must specify the decision against which the appeal is being brought, must include a summary of the facts and pleas relied upon, must state the subject-matter of the application, and must contain a schedule of the documents on which the appellant intends to rely. If the appellant resides abroad, the appeal must in addition give an address for service in Luxembourg. The original and four copies of the notice of appeal, duly dated and signed, must be lodged with the Court Registry, accompanied by the contested notice of assessment and the documents listed, in quadruplicate.

You are required by law to refer the disputed matter in the first instance to the Director of the Administration des contributions directes. If you fail to do so, the Tribunal administratif will declare your application inadmissible.

You may:

• represent yourself;
• arrange to be represented by:
  • a lawyer,
  • a chartered accountant (expert-comptable), or
  • a company auditor (réviseur d'entreprises),

      duly authorised to practise his/her profession.

An appeal may be lodged against the judgment of the Tribunal administratif (Administrative Court) before the Cour administrative (Higher Administrative Court) (time-limit: 40 days).

No right of appeal lies against the decision of the Cour administrative.

A distinction needs to be drawn between:

• objective equity, which is designed to rectify a rule or norm that proves to be unjust in a particular case, by reason of the fact that it results in taxation running counter to the intention of the legislature, and
• subjective equity, involving the personal situation of the taxpayer, where payment of the tax would have the effect of compromising his/her economic existence and depriving him/her of essential means of subsistence.

• A non-contentious appeal does not involve any dispute as to the lawfulness of the notice of assessment; it is limited to a plea for consideration to be given to questions of equity.
• By contrast, disputes concerning the application of the law, the evaluation of the taxable base or the omission of a deduction fall within the jurisdictional framework of contentious judicial proceedings.

You should address your request to the Director of the Administration des contributions directes (ACD).

Your request must be submitted by no later than the end of the year following the year in which the events prompting you to make the request took place.

In principle, objective rigour applies as from the date of your notice of assessment, and subjective rigour as from the time when real, ongoing financial difficulties are found to exist which are such that you are no longer able to pay your tax debts.

Your request for tax forgiveness must contain: 

• your name, address and tax number;
• in the context of objective rigour, a statement and substantiation of the reasons why you consider that the law does not correspond to your specific, particular case;

in the context of subjective rigour, details of your monthly income and expenses, and of your assets, showing that you are unable to pay the tax that you owe.

Your request for tax forgiveness must be in writing and must be sent to the Director of the Administration des contributions directes (ACD).

You may express yourself in one of the three official languages of the Grand Duchy of Luxembourg, namely Luxembourgish, French or German.

The Director’s decision on your request for tax forgiveness will be formulated, in principle, in the language chosen by you.

The Director of the Administration des contributions directes may either reject your request for tax forgiveness or declare it to be well founded.

The Director’s decision may be the subject of an application for reversal of such rejection, to be lodged within three months before the Tribunal administratif (Administrative Court). An appeal against the judgment of the Tribunal administratif may be lodged before the Cour administrative (Higher Administrative Court) within 40 days after notification thereof.

In the absence of a decision by the Director within six months following submission of the request for tax forgiveness, it may be regarded as having been rejected, and you have the right to lodge an application for reversal of such rejection before the Tribunal administratif.

However, following the expiry of that six-month period, the matter does not necessarily have to be brought before the Tribunal administratif, as the Director’s decision may still be issued after that period has expired.

You are obliged by law to submit your request in the first instance to the Director of the Administration des contributions directes. If you fail to do so, the Tribunal administratif will declare your request inadmissible.

You may:

• represent yourself;
• arrange to be represented by:
  • a lawyer,
  • a chartered accountant (expert-comptable), or
  • a company auditor (réviseur d'entreprises),

      duly authorised to practise his/her profession.

An appeal may be lodged against the judgment of the Tribunal administratif (Administrative Court) before the Cour administrative (Higher Administrative Court) (time-limit: 40 days).

No right of appeal lies against the decision of the Cour administrative.

You can apply for an income certificate from the territorially competent tax office. The application can be made either by telephone or via the contact form of the Administration des contributions directes (ACD). The income certificate may either be collected directly from the competent tax office during opening hours (7.45 to 12.15) or sent by post to the applicant’s registered address.

The application to the ACD must contain:

1. the applicant’s surname and first name(s);
2. the applicant’s file number/identification number (matricule);
3. the applicant’s address;
4. the name of the authority demanding the certificate and the reason for the request.

To find a particular office, please click on the following link: Compétences et adresses - Profil de l'Administration - Administration des contributions directes - Luxembourg (public.lu)

An application for a certificate of fiscal domicile must be made to the competent tax office either by post or via the contact form of the Administration des contributions directes (ACD), stating the reason for the application and the name of the organisation demanding the certificate.

We also recommend that you state the language in which the certificate is to be drawn up, namely French, German or English.

The certificate of ownership or non-ownership is drawn by the Real Estate Valuation Section (SEVI). You can apply for it by telephone, e-mail or post.

To find the telephone number or e-mail address of the SEVI, please click on the following link: Section des évaluations immobilières (SEVI) – Compétences et adresses - Contact - Administration des contributions directes - Luxembourg (public.lu)

The offices are open to the public Monday to Friday from 7.45 to 12.15. In the afternoon, they are open by appointment between 13.15 and 17.00.

Further information concerning the opening and closing times of the offices can be found by clicking on the following link: Heures d'ouverture et de fermeture des bureaux - A à Z - Administration des contributions directes - Luxembourg (public.lu)

To find a particular office, please click on the following link: Compétences et adresses - Profil de l'Administration - Administration des contributions directes - Luxembourg (public.lu)

For all general questions concerning the taxation of natural persons, you can contact the ACD either by telephone or by e-mail or via the contact form appearing on its website.

You can also attend in person at its offices during opening hours (Monday to Friday from 7.45 to 12.15). In the afternoon, they are open only by appointment between 13.15 and 17.00.

To find the telephone number of a particular office, please click on the following link: Compétences et adresses - Profil de l'Administration - Administration des contributions directes - Luxembourg (public.lu)

In Luxembourg, the national identification number of a natural person is also known as his/her “matricule” or “numéro d’identification personnelle” (NIF – personal identification number). The personal identification number of a natural person is composed of 13 digits. In the context of direct taxation, this “matricule” may also serve as the tax identification number (NIF/TIN) for natural persons.

The national identification number in Luxembourg of a legal entity is likewise known as its “matricule” or “numéro d’identification personnelle” (NIF – personal identification number). It is composed of 11 digits. In the context of direct taxation, this “matricule” may also serve as the legal entity’s tax identification number (NIF/TIN). Its structure reflects the year of formation of the legal entity and its legal form, whilst the last five digits are random, thus: YYYY FF XX XXX.

This 11-digit personal identification number must be stated in all communications with the competent offices of the ACD and on all bank transfers in favour of the Administration des contributions directes (ACD).

Please consult the following link: Service de recette - Profil de l'Administration - Administration des contributions directes - Luxembourg (public.lu).

You just need to click on the competent tax collection department to find your file.

You can apply for individual assessment using form 166 (for resident and non-resident taxpayers) appearing on the website of the Administration des contributions directes (ACD). The completed form must be sent to the competent RTS office together with the supporting documents referred to in form 166. Additional documentation may be requested by the competent RTS office.

The ACD recommends the application made via the online procedure without Luxtrust authentication (Demande d’individualisation / taux RTS) available on Guichet.lu.

Taxpayers (or employers) encountering problems with a Luxtrust product (token, smartcard, Luxtrust mobile) should contact the Luxtrust helpline on: (+352) 24 550 550.

In the event that the data entered are not recorded, or the automatic amounts are not displayed, you should save the form on your hard drive and then manually start Acrobat Reader and open the form thus saved.

If you encounter problems in filling out, displaying or saving the income tax return form appearing on the website of the Administration des contributions directes, you can download the following tutorial in different formats:

Remplir une déclaration d’impôt avec l’assistant électronique — Guichet.lu - Guide administratif - Luxembourg (public.lu)

If the problem persists, you can contact the Guichet.lu Helpdesk via the link Contact Helpdesk — Guichet.lu - Guide administratif - Luxembourg (public.lu)

If you have technical questions concerning the XML format, you can contact the IT Division of the Administration des contributions directes (e-mail address: decl.pph@co.etat.lu).

To resolve problems relating to the tax cards database, employers can get in touch with the IT Division of the Administration des contributions directes (ACD) by sending an e-mail to the following address: fpe@co.etat.lu.