Luxembourg Company Register: Searching the RCS, RESA and RBE

Luxembourg Business Registers and the Registers It Keeps

The Luxembourg company register is the Trade and Companies Register, the registre de commerce et des sociétés (RCS), and a Luxembourg company register search is made at lbr.lu, the site of Luxembourg Business Registers (LBR). LBR is an economic interest grouping of the State, the Chamber of Commerce and the Chamber of Crafts, working under the Minister of Justice. It has kept the RCS since 23 January 2003, has run the RESA gazette since 1 June 2016 and holds the Register of Beneficial Owners (RBE) under the Law of 13 January 2019. The RCS law of 19 December 2002 makes the register public and requires its entries to be adequate, accurate and current. This page explains what each register shows and how to read a file before buying an S.à r.l., the SARL. Our Luxembourg overview covers the rest.

The RCS Number: the Letter B and “R.C.S. Luxembourg”

For an S.à r.l., as for an SA, an SCSp, an SCA or the branch of a foreign company, the RCS number is the letter B followed by digits; LBR’s search box gives B123456 as its example, and non-profit associations carry numbers beginning with F. Every document of an S.à r.l. must show “R.C.S. Luxembourg” followed by the number, which also tells it apart from France’s similarly named register. In the EU business register network the company is known by its EUID, built from the number: LURCSL.B101818 for B101818. The RCS number is not a tax or VAT number; our guide to the company registration number compares these identifiers across countries.

What the Free Search on lbr.lu Shows

The public search runs on a company’s current or former name, abbreviations included, or on its RCS number, and marks companies struck off as “radiée”. A file opens without any login on the name, RCS number, registered office, registration date and legal form, followed by four tabs:

Tab	What it shows	Access
Additional information	Trade names, NACE activity code, EUID	Open to anyone
Publications	Every RESA publication, with its number, date, type and the data changed: managers, partners, object, capital	Open to anyone
List of filings	Every document filed with the RCS, downloadable in PDF as filed, annual accounts included	After an anonymous connection (a security question and the State’s usage conditions) or an electronic ID
Beneficial owners	The RBE entry	Only for users signed in with a LuxTrust or eIDAS certificate and entitled to RBE access

Consulting publications and filings has been free since 1 June 2016. Under Article 6 of the 2002 law the file of an S.à r.l. also records its object, capital, managers with their signing powers, and partners with the number of shares each holds.

LBR Extracts and Certificates

Certified documents are paid. They are ordered on lbr.lu after the same anonymous connection or an electronic ID, and issued with a qualified electronic signature or on signed secure paper.

• RCS extract: the public data in the file, certified by the register. At least one Luxembourg bank asks an existing company for RCS and RBE extracts under three months old.
• Negative certificate: confirms that no court ruling is registered in the RCS for the company.
• RBE extract: issued within the access rules below; the company may order one of its own entry.
• Certificate of trade name availability: issued in French only.

RESA, the Gazette That Replaced the Mémorial C

The Recueil électronique des sociétés et associations replaced the Mémorial C on 1 June 2016, whose archive stays reachable from the RCS site. It is a daily journal that anyone can read free of charge without logging in. A document appears on the day it is filed or on a date the filer chooses within 15 days, under a reference such as RESA_2026_204.271, and in one of three forms: in full, as with the incorporation deed of an S.à r.l.; by extract, giving only what the law requires; or by mention, giving only the subject and date of the filing, which is how annual accounts and coordinated articles appear. Since every change of partner or manager is published, the Publications tab is the company’s history.

The RBE Since the Ruling of 22 November 2022

The RBE records each individual holding more than 25% of the shares, voting rights or capital of an S.à r.l. or controlling it by other means, and failing one, its senior managing official: name, nationality, date and place of birth, country of residence, address, identification number and the nature and extent of the interest. The company files the data, and each change, within one month.

The RBE was open to the public from 1 September 2019. LBR suspended public access on 22 November 2022, the day the EU Court of Justice struck down the directive provision opening these registers to any member of the public (Joined Cases C-37/20 and C-601/20). Under Article 11 of the Law of 13 January 2019, as amended by the law of 23 January 2025, access is open to national authorities and public bodies authorised by law, professionals carrying out anti-money-laundering checks, self-regulatory bodies, and persons with a legitimate interest in fighting money laundering, which the law says includes journalists, EU anti-money-laundering non-profits and persons likely to transact with the company. Apart from the national authorities, users see neither addresses nor identification numbers and must record the reason for each consultation, and a likely counterparty sees only the company concerned. A company consults its own entry with an access code.

Filed Annual Accounts of an S.à r.l.

The partners approve the accounts within six months of the year end, and after validation on the eCDF platform they are filed with the RCS within one month of approval, so no later than seven months after the year end. The RESA carries only a mention of the filing; the accounts are read in PDF in the list of filings. Three Luxembourg rules shape what a reader finds:

• Annual accounts may be drawn up in French, German or English, while most other filings must be in French, German or Luxembourgish.
• A small company may publish an abridged balance sheet and notes and leave out its profit and loss account, management report and auditor’s report.
• For an S.à r.l. formed since 2 June 2026, the partners who have not fully paid up their shares are listed after the balance sheet.

Repeatedly failing to make the legal RCS publications breaches, under the business permit law, the professional integrity of the dirigeant on whom the permit rests, and the Luxembourg bankers’ association warns that late accounts can harm the banking relationship. See our page on bank accounts for Luxembourg companies.

Checking an S.à r.l. on the RCS Before Buying It

A ready-made S.à r.l. changes hands by a transfer of its shares, so everything in its file comes with it. Before signing, read the file the way a Luxembourg bank will after the purchase:

• Identity. B number, name, legal form, registered office and registration date match the documents offered, with no “radiée” mark.
• Partners and managers. The partners and shareholdings on record match the seller’s title, and the Publications tab accounts for every change.
• Accounts. A set filed for each financial year within seven months of its end and, for a company formed since 2 June 2026, no partner listed as owing unpaid capital.
• Court and insolvency entries. A negative certificate, and REGINSOL, LBR’s insolvency register, which also lists administrative dissolutions without liquidation, a procedure the public prosecutor can start against a company with no assets and no employees that seriously breaches commercial or company law.
• Registered office. No published dénonciation de siège, by which a domiciliation agent ends the company’s seat. LBR reminded companies on 7 October 2026 that the RCS address must match the National Register of Localities and Streets and be able to receive post.
• Beneficial owners and a fresh extract. An RBE extract the company orders of its own entry, and an RCS extract dated shortly before signing.

After the purchase, the new partner and managers are filed with the RCS and published within one month, and the new beneficial owners entered in the RBE within one month. The share transfer, which can be signed without a notary, is explained on our page on ready-made shelf companies in Luxembourg; when a new company fits better, see company formation in Luxembourg. The Luxembourg guide is also available in Russian. LBR keeps the registers and issues every extract; our part is to prepare the transfer or formation documents and the RCS and RBE filings that follow.

Frequently Asked Questions about the Luxembourg Company Register

Is the Luxembourg company register search free?

Yes. Searching lbr.lu by name or RCS number, opening a company’s file and reading RESA publications are free, and filed documents, annual accounts included, are free to consult after an anonymous connection. RCS extracts, certificates and certified copies are paid, and the beneficial owners tab needs a LuxTrust or eIDAS certificate and a legal right of access.

How do I find the RCS number of a Luxembourg company?

Search the company’s name on lbr.lu: the results list each match with its RCS number, and a commercial company such as an S.à r.l. has a number beginning with B. The number also appears on the company’s letters and invoices after the words “R.C.S. Luxembourg”.

Can I see who owns a Luxembourg S.à r.l.?

Its legal owners, yes. The RCS records the partners of an S.à r.l. and the number of shares each holds, and every change of partner is published in the RESA. Its beneficial owners are in the RBE, closed to the general public since 22 November 2022 and open to authorities, anti-money-laundering professionals and persons with a legitimate interest.

Is the Luxembourg company register available in English?

The lbr.lu portal and its help pages work in English, but filings must be in French, German or Luxembourgish. A company may add translations into any official EU language, and the original prevails if the two differ. Annual accounts are the exception, as they may be drawn up in English.

What is the difference between the RCS and the RESA?

The RCS is the register itself: the recorded data on each company and every document filed with it. The RESA is the official journal where documents the law requires to be published appear, in full, by extract or by mention, on the filing day or a chosen date within 15 days.