The glossary to understand and take action

Tax support

Tax support organises the monitoring of obligations and analysis of the company's tax issues in accordance with the agreed engagement.

Notion comptable, fiscale ou juridique · Luxembourg Fiduciaries Editorial Team · Reviewed on

Understand the scope

Definition and points to distinguish

Specify the taxes, periods and countries covered. Monitoring the company does not automatically include the personal tax return of its director.

In your file

What this changes in practice

Tax support organises the ongoing monitoring of obligations and analysis of the company's events. It may combine a timetable, preparation of returns, responses to requests and advice on new transactions. Its scope varies according to the engagement. To be useful, the firm must be informed sufficiently early of changes in activity, foreign transactions and important decisions, not only when a return is due to be filed.

A scenario to help you understand

Educational example

A company enters a new foreign market. It informs its tax contact before issuing its first invoices in order to verify the place of supply, VAT and any obligations, rather than waiting for the annual closing.

Fictitious situation, presented to illustrate the concept.

Prepare for what comes next

Points to check

  • Préciser les impôts couverts par la mission
  • Partager les changements d’activité
  • Séparer préparation, validation, dépôt et paiement

The practical question

Find out more

Quels documents rendent le suivi fiscal plus efficace ?

Un calendrier des obligations, les déclarations déposées, calculs, avis, paiements et échanges avec l’administration constituent une base utile. Signalez les opérations inhabituelles avant la clôture, notamment internationales ou intragroupe. Le suivi doit permettre de comprendre les positions retenues et les questions ouvertes, pas seulement de retrouver un formulaire envoyé plusieurs mois auparavant.

Connecting concepts

Terms to know as well

Continue with the concepts, contacts and procedures related to this topic.

Tax adviceTax advice consists of analysing the tax consequences of a situation and explaining the applicable options and obligations.Tax returnA tax return provides the administration with the information needed to assess or verify a tax for a given person and period.Corporate taxationCorporate taxation encompasses the taxation and filing rules applicable to a company and its transactions.Corporate income tax (IRC)The term corporate tax commonly refers to the taxation of companies’ profits; in Luxembourg, IRC is one of the taxes to be distinguished.Municipal business taxMunicipal business tax (ICC) is a direct tax linked to commercial profit, the calculation of which notably takes account of a municipal rate.Tax return — Form 500Form 500 refers to the tax return form for entities, with the sections and appendices corresponding to the relevant year and situation.

Put it into practice

Explore further with our guides

Practical guideCorporate tax return: prepare the documents and monitor filing

Sources and verification

References consulted on 20 September 2026. Official procedures specify the applicable conditions and exceptions.

This guide explains a general process. The applicable rules depend on your situation; it does not constitute personalised advice. Report a correction.

A definition gives you a reference point. To examine your situation, clarify your question with a professional.