Quarterly tax advances in Luxembourg: the calendar
Quarterly tax advances in Luxembourg do not follow the current year's result: they reproduce a quarter of the latest assessment. A company whose profit collapses keeps paying on the old basis.
What are the quarterly tax advances in Luxembourg?
Quarterly tax advances in Luxembourg are set by the tax office for income tax, for municipal business tax and, for companies that are not fiscally transparent, for net wealth tax; they fall due on 10 March, June, September and December for corporate income tax, and on 10 February, May, August and November for the other two.
The split surprises anyone arriving from another country: the four dates are not the same from one tax to the next. A Luxembourg capital company therefore faces eight due dates per tax year rather than four, and the two series follow each other without ever coinciding.
These advances are neither a voluntary instalment nor an option. Article 135 of the amended law of 4 December 1967 on income tax sets their due dates, and fixing assessments and advances alike is a matter for the tax offices. The balance comes only afterwards: the assessment notice states what remains due once the advances already paid are taken into account, with a settlement period of, in principle, one month from its issue.
The scope of the three taxes and the single form that carries them are set out on our corporate tax return page.
| Tax | Advance due dates | Balance |
|---|---|---|
| Corporate income tax | 10 March, 10 June, 10 September, 10 December | After receipt of the assessment notice |
| Municipal business tax | 10 February, 10 May, 10 August, 10 November | After receipt of the assessment notice |
| Net wealth tax | 10 February, 10 May, 10 August, 10 November | After receipt of the assessment notice |
How is the amount of a quarterly advance calculated?
The amount of the advance is set, in principle, at one quarter of the tax which, after crediting taxes withheld at source, results from the most recently established assessment. The basis is therefore always the past, never the result of the current financial year.
The consequence is mechanical and works both ways. An exceptional year feeds four advances of the following year even though activity has already returned to its usual level; conversely, a company that has stopped making a profit keeps paying on the last known assessment for as long as nobody asks for anything else.
Two correction routes exist, and only one depends on the taxpayer. The amount is changed either on the taxpayer's reasoned request, or of the authorities' own motion where the Luxembourg Inland Revenue holds elements justifying a reduction or an increase of the advance. Waiting for the second amounts to hoping the administration will guess a change it has no reason to know about.
The quarter is computed on the tax of the latest assessment, whatever that tax is made of. Where the assessment came down to the minimum net wealth tax, the advances reproduce that minimum: its scale is set out in our article on the minimum net wealth tax.
How to have advances revised: reasoned request and complaint
A revision of advances in Luxembourg is obtained through a duly reasoned written request addressed to the competent tax office, by post or through the contact form on the Luxembourg Inland Revenue website. No particular form is imposed, but the request must carry a reason.
What makes it useful is the document attached to it. An interim statement, draft annual accounts, the loss of the closed financial year or the cessation of an activity are verifiable elements; the announcement of a difficult year, on its own, is not. We systematically attach the latest closed trial balance, because it is the only document that ties the assertion back to the file.
Revision is not the only tool. An assessment notice fixing advances can be challenged by a complaint, to be lodged within three months with the director of the Luxembourg Inland Revenue, who has six months to answer; where the decision is unsatisfactory, an appeal for reversal lies within three months before the Administrative Tribunal.
The case we see regularly, however, is not the advance that is too high but the advance nobody expected. A company whose first assessment arrives late discovers at the same moment the advances of the current year and the catch-up for earlier years, although the charge was foreseeable as soon as the accounts were closed. That is why we provide for advances at closing, not on receipt of the assessment notice.
An advance paid late costs 0.6% per month
A tax advance paid late in Luxembourg produces late payment interest of 0.6% per month, which starts to run on the first day of the month following the month in which the advance fell due. The month of payment counts as a full month, whether the transfer leaves on the 1st or on the last day of that month.
A payment extension can be requested, in writing and duly reasoned, with supporting documents, from the competent office of the Luxembourg Inland Revenue. It is not a right but a favour, assessed file by file. Where it is granted, interest is reduced to 0.1% or 0.2% per month depending on the period; missing one instalment date makes the full rate run on the remaining balance.
Non-payment then follows a short sequence. The collection office issues a first notice to pay within five days, then a second and final notice within five days; where these remain without effect, they open forced recovery by way of a constraint, rendered enforceable by the director of the Luxembourg Inland Revenue or their delegate.
Eight due dates a year, two of them concentrated in the same quarter, are planned as a fixed charge rather than met as a surprise: that is the object of the monitoring described on our cash management page.
| Situation | Consequence |
|---|---|
| Advance not paid when due | Late payment interest of 0.6% per month, from the first day of the following month |
| Month of payment | Counted as a full month, whatever the date of the transfer |
| Payment extension granted on reasoned request | Interest reduced to 0.1% or 0.2% per month depending on the period granted |
| Instalment date missed | Full rate of 0.6% per month on the remaining balance |
| Notices left without effect | Two five-day notices, then an enforceable constraint |
Paying an advance: collection office, file number, year
An advance is paid by bank transfer to the account shown on the statement of account that follows the assessment notices, the Luxembourg Inland Revenue also publishing the bank details of its collection offices in Luxembourg, Esch-sur-Alzette and Ettelbruck.
The reference is no formality, it is the key that attaches the payment. The transfer must state the type of tax, the file number for a taxpayer assessed as an entity, and the tax year concerned. Without those three elements, the collection service cannot allocate the amount to the due date the company believes it has settled.
The most ordinary mistake is therefore not the missed payment but its allocation: a municipal business tax advance paid under the corporate income tax reference leaves an apparent debt on one side and a dormant credit on the other, with late payment interest running on the first.
Tracking the eight due dates, checking the statements of account and asking for a revision at the right moment belong to the recurring calendar described by our pricing page.
Crediting overpayments and advances under tax consolidation
Quarterly advances paid and taxes withheld at source are credited against the tax established by assessment, and the excess is refunded on the basis of article 154 of the income tax law. An advance that proves too high is therefore not lost.
What is lost lies elsewhere. An excessive advance ties up cash for the whole period between its due date and the issue of the assessment notice, whereas the late payment interest produced by an unpaid advance stays with the State for good. That asymmetry between the two situations is the real reason to watch the level of the advances.
Under the tax consolidation regime, the parent company is liable for the corporate income tax corresponding to the taxable income realised by the group as a whole, and it is that company which must pay the advances of this tax on the due dates of article 135, as the circular of the director of taxes L.I.R. no. 164bis/1 of 27 September 2004 recalls.
The rule quoted covers corporate income tax alone. The treatment of municipal business tax and net wealth tax advances of the consolidated companies does not follow from it: on that point, the position of the competent tax office is to be confirmed file by file before removing a payment from a group calendar.
Sources and verification
Written for Financial Services Luxembourg and reviewed before publication by Mickaël LOC, licensed accountant (authorisation 10077274). The due dates, rates, procedures and references in this article were verified on 13 September 2026 against the official sources listed below.
On the Luxembourg Inland Revenue side: the "Avances d'impôt" page for the amount set in principle at one quarter of the tax resulting from the most recently established assessment after crediting taxes withheld at source, and for its amendment on the taxpayer's reasoned request or of the authorities' own motion; the tax calendar for the due dates of 10 March, 10 June, 10 September and 10 December for corporate income tax and for the first quarterly net wealth tax advance of entities on 10 February; the page on additional levies for failure to observe filing and payment deadlines for the rate of 0.6% per month, its starting point on the first day of the month following the due date and the month of payment counted in full; the "Délais de paiement" page for the written and reasoned request, its character as a favour, the reduced interest of 0.1% or 0.2% per month and the loss of the benefit of instalments; the page on the deadlines of the various remedies for the three-month complaint before the director, covering in particular assessment notices fixing advances, the six months allowed for an answer and the three months for the appeal for reversal; the page on crediting advances and taxes withheld at source for the credit and the refund of the excess; the page listing the bank details of the collection offices; and the circular of the director of taxes L.I.R. no. 164bis/1 of 27 September 2004 for the parent company's duty to pay the advances on the due dates of article 135. On the guichet.lu side: the pages on corporate income tax, municipal business tax and net wealth tax for the tax office's power to fix quarterly advances, for the due dates of 10 February, 10 May, 10 August and 10 November and for the balance payable after receipt of the assessment notice, together with the page on forced recovery for the two five-day notices and the constraint.
Four limits must be flagged. The text of article 135 of the amended law of 4 December 1967 was not read in its primary source: the PDF files of the Luxembourg Inland Revenue and legilux.public.lu are unreachable from our drafting environment, and those texts were consulted through indexed extracts. The exact match between the length of the payment extension granted and the reduced rate of 0.1 or 0.2% per month could not be established, nor could the division competent to receive the request, assessment or collection: the article therefore keeps a neutral wording. The treatment of municipal business tax and net wealth tax advances under the tax consolidation regime is not verified and is not asserted. Lastly, the existence of an amount below which no advance is fixed could not be established and is therefore not quoted. Readers can confirm these points on legilux.public.lu, on impotsdirects.public.lu and with the competent tax office.
This article states the law as it stands at the date of publication. Due dates, rates and procedures change, and any decision binding your structure must be checked on the date you rely on it. Report an error to contact@financialservices.lu: the correction is dated in the article.
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