An invoice is an accounting document that records the terms of purchase and sale of products, goods or services supplied.

An invoice issued by a self-employed professional is called an fee note.

Issuing a proper invoice is essential, as it:

• serves as a supporting document for accounting entries;
• is used to establish the amount of VAT (value added tax) to be deducted or paid;
• constitutes evidence for the recovery of debts.

Who is concerned

Invoices are issued by:

• any person subject to VAT;
• any person trading under their own name or any commercial company that sells goods or provides services to another registered VAT taxpayer.

For relations with consumer customers, it is not compulsory to issue an invoice, but it is nevertheless recommended that one be issued, in particular to record proof of the transaction carried out.

It is not customary to issue invoices for purely private and non-recurring transactions.

Deadlines

Transactions between professionals

In transactions with a professional, the seller or service provider must issue the invoice:

• at the latest on the 15^th day of the month:
  • following the month where the delivery of goods or services took place;
  • during which the delivery of goods or services took place in the event of periodic billing; or
• at the latest upon payment of the deposit, if applicable.

However, a trader is free to issue an invoice sooner.

Any document which modifies the initial invoice in a specific and unequivocal manner is considered to be a new invoice.

Debtors, for their part, are bound by the contractual payment deadlines, or failing this, the legal payment deadlines.

In the event of late payments, the seller/service provider is entitled to claim late-payment interest.

Transactions with a consumer

In the context of a transaction with a consumer, the seller or service provider may, if applicable, claim late payment interest. To do this, applicants must:

• issue the invoice within a month of receipt of the goods by the client, of completion of the works or provision of services;
• clearly state on the invoice that the legal rate of late payment interest will be applied where necessary.

The debtor must comply with the legal payment deadlines, otherwise the seller/contractor can claim late payment interest.

How to proceed

Form

Invoices can be issued on paper or as an electronic document (e-invoice).

They must be drawn up in 2 copies, one for each party.

Mandatory information

Information concerning the business

An invoice must include the following information:

• the identification of the seller or service provider, namely:
  • the company name and/or trading name;
  • the legal form of the business;
  • the exact address of its registered office;
  • the wording "Registre de commerce et des sociétés, Luxembourg" (Trade and Companies Register, Luxembourg) or the initials "R.C.S. Luxembourg" followed by the registration number (does not apply to cooperative companies);
  • its business permit number.
  • for limited liability companies and simplified limited liability companies the indication of the company capital is also mandatory.
  • for craftsmen and traders working in their own name: their profession and their business permit number.
• the identification of the client;
• the date of the sale or service provision;
• the date of the invoice;
• a sequential number, based on one or more series, uniquely identifying the invoice;
• the quantity and precise name of the transaction concerned;
• any price reductions;
• the payment deadline;
• discount conditions, if applicable;
• penalties for late payment, if applicable;
• the unit price excluding VAT of products sold or the hourly rate excluding VAT of services rendered;
• the legally applicable VAT rate and the corresponding total amount of VAT or, where appropriate, a reference to the benefit of an exemption by referring to the relevant legal provision;
• if the invoiced amount exceeds EUR 100 including all taxes, it must in addition contain:
  • the VAT number of the seller;
  • where applicable, the VAT number of the client;
  • where applicable, the VAT number of the tax representative;
  • the tax base for each rate or exemption, the unit price before tax and any discounts, rebates or refunds if these are not included in the unit price;

In addition to the mandatory information, the invoice must contain, where appropriate, the following additional information:

• 'auto-liquidation' (reverse charge mechanism) where the buyer or client is liable for VAT;
• 'comptabilité de caisse' (cash basis accounting) where VAT becomes chargeable at the time of payment of the invoice;
• 'auto-facturation' (self-invoicing) when the client issues the invoice instead of the supplier or provider;
• 'régime particulier - agences de voyage' (special scheme for travel agencies) for the application of the special scheme for travel agencies;
• 'special scheme - (name of scheme)' for the application of the special profit margin scheme for the supply by a taxable dealer:
  • 'second-hand goods';
  • 'art objects';
  • 'collector's items or antiques';
• 'intra-EU supply of a new means of transport'.

In order to invoice excluding VAT the provision of services or supply of goods to professionals (B2B) in another EU Member State, the seller has to:

• first, check the validity of the client's VAT number in the VIES VAT number validation database on the website of the European Commission;
• where possible, print and keep the results page with the client's VAT number and date of verification;
• indicate the client's valid VAT number on the invoice.

VAT payers are required to keep a duplicate of all invoices issued.

Optional information

Invoices can detail the terms of payment. Failing this, the invoice is payable immediately, within the legal deadlines.

In the framework of transactions between professionals and in the absence of contractual provisions on payment deadlines and late payment interest, it is recommended to indicate on each invoice that late payment interest at the legal rate will apply in the event of late payment.

In the case of transactions with consumers, the invoice must contain an explicit statement that the trader intends to claim statutory interest for late payment if payment is not made before the set due date.

The concept of the accepted invoice

Between traders, the existence of a contract can be proven by an accepted invoice, whether acceptance is express or implied.

An invoice is deemed to have been accepted in the event of unconditional payment or silence from the buyer's side which goes beyond the time frame required to check the invoice, its terms and the goods to which it relates.

Failing legal provisions in this matter, the courts generally deem that an invoice has been accepted after a period of 4 to 8 weeks.

Certain jurisdictions have occasionally even ruled that mail exchanges between traders that have not given rise to a written dispute are deemed to have been accepted as regards their content.

Buyers can rebut this presumption by proving that:

• they have disputed the invoice in due time; or
• their silence is not related to the acceptance of the invoice.

Disputing an invoice

Invoices and other commercial documents must be checked immediately upon receipt.

If an invoice or any other commercial document is not well-founded, the trader must dispute it, preferably in writing, failing which he may be bound by the concept of the accepted invoice (or mail).

Disputes must be formulated in a clear and precise fashion.

Who to contact