The Luxembourg naming rule is one line: the name must be different from that of any other existing company. You test a name by submitting an electronic request for a certificate of name availability to Luxembourg Business Registers before incorporating. The fee published on guichet.public.lu is €4.75–10. The certificate is valid from the moment it is issued until the name is entered in the RCS — but it does not reserve the name: any available name may be taken by the first person who requests it when registering with the RCS. Only RCS registration, at €10–106 depending on legal form, makes the name yours.
With no company yet, securing a name takes three pieces of work, in this order: the name check, the deed and the RCS registration.
See what company formation includes, from €899What does the certificate actually prove?
The scope is narrower than the document's name suggests: it attests whether the requested name or names are available compared with the names of persons already registered with the RCS. That is one comparison, against one dataset, on one day: the entities already on the trade and companies register (Registre de commerce et des sociétés, RCS) when you ask.
It is not a trademark search, not a domain check and not clearance to operate. The issued certificate stays downloadable from the LBR portal for 20 days.
| Step | What it establishes | What it does not do | Fee at the register |
|---|---|---|---|
| Name-availability certificate | the name is free against RCS-registered names, at that moment | reserve or block the name | €4.75–10 |
| RCS registration of the company | the name as filed and published, first request served first | give any brand right | €10–106, depending on legal form |
| Trademark filing (Benelux or EU) | rights in the classes you apply for | make a name available at the RCS | none at the RCS |
Guichet publishes the certificate fee as an administrative fee. The grand-ducal tariff regulation behind the register's charges prices a paper certificate at €10 and an SA's registration at €105.91. One difference matters: the RCS tariffs set by grand-ducal regulation are stated exclusive of VAT and are subject to VAT at 17%. Budget from the total in your LBR basket, not from a tariff line.
Why is an available name not a reserved one?
A certificate issued on Monday does not stop a competing incorporation filed on Wednesday, because the register serves whoever reaches it first. What you hold is evidence of what was free on the day the certificate was issued, not a claim on the name.
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A competing filing can land in the gap between choosing a name and filing the deed: the days spent on articles, capital and signatures. Keep two or three alternates live through that gap. A collision found after the deed is drafted means redrafting it.
Near-misses are the awkward case. "Lux Consult" and "LuxConsult" differ only by a space, and the check compares the string you submit. It does not tell you in advance how much difference is enough, so a variant you did not test can still be refused at registration. One request can cover several names, so put the variants in the same request and settle them together.
Does the check screen banned words or trademarks?
No. The request runs the comparison against registered names and nothing else. It is a check on collisions, not a vocabulary filter that tests your wording against banned or reserved terms.
For a name that implies banking, insurance or fund business, a clean certificate says nothing about whether you may carry on that activity under it.
Trademarks are not in the register's dataset either, so a clean certificate does not cover them. They are filed and examined at the Benelux Office for Intellectual Property or at EU level, and neither office consults the RCS. Run the trademark search beside the register search while the name is still a draft.
Does the legal form have to be in the name?
No. The duty to show the legal form attaches to what the company issues, not to the name it registers. For a Sàrl, the company's documents must state the company name, the words 'société à responsabilité limitée', the registered office, the RCS registration number and the capacity of the signatory of the document (the share capital mention is no longer obligatory). For a Sàrl-S, the name must appear on all company documents followed by the mention SARL-S.
So a Sàrl whose registered name carries no suffix is not defective, as long as its letterhead, invoices and contracts carry the mentions. A template written before the rule changed may still print the share-capital line, which is no longer obligatory.
For a Sàrl-S, the RCS filing covers the company or trading name and any abbreviation and business sign used, the legal form and any additional mention required by law, the precise address of the registered office, the corporate object and the amount of the share capital. The capital therefore sits in the register's own record, whether or not a given document repeats it.
Nor is the suffix what separates two companies. A name identical to a registered one, with only a different legal form, is a fragile plan. The difference has to be in the name itself.
Can I change the name later?
Yes, but it is a statute amendment, not a settings change. At the register, filings are made electronically, and the amendment is due within 1 month of signing. Publication follows: the deed is published in RESA on the day of filing, or on a fixed date chosen by the filer when creating the filing request, within a limit of 15 days after filing.
Publication is the moment the new name becomes public and searchable. Until then the choice is private, so register domains and handles before the filing, not after it.
What to do before the deed is signed
Each of these steps is cheap while the name is still a draft, and none of them reserves it.
- Search the RCS for collisions and near-misses, and write down two or three alternates before you get attached to one.
- Send the electronic availability request to Luxembourg Business Registers, budget €4.75–10, read the basket total before you confirm, and download the certificate within 20 days.
- Run a Benelux and EU trademark search in parallel if the brand will carry value.
- Read the name aloud in French and German, because an unfortunate second meaning surfaces fast in a three-language market.
- Register domains and handles while the name is still private.
Only the register settles it. The name is yours once the RCS enters the company, for a registration fee of €10–106 depending on legal form. That is why drafting the articles, signing the deed and filing the RCS registration should follow the certificate within days, not weeks.