Frequently asked questions

The new law, which came into force on 18 December 2021, defines an electronic invoice as: "an invoice that has been issued, transmitted and received in a structured electronic form that allows its automatic and electronic processing, any equivalent request for payment that meets these same conditions or any document or message that modifies the original invoice and refers to it in a specific and unambiguous way that meets these same conditions, i.e. a file that is XML or contains XML and not simply an unstructured PDF, Word or other document and therefore does not contain all the elements of the invoice as separate and standardized attributes that can be automatically read by a computer".  

All economic operators who send invoices to the public sector within the framework of public procurement and concession contracts are concerned, regardless of the sector of activity. Public procurement does not only concern tenders, but all invoices issued to a public sector body, without any lower limit.  

What is public procurement? 

Contracts for pecuniary interest concluded in writing between one or more economic operators and one or more contracting authorities and having as their object the execution of works, the supply of products or the provision of services (Art. 3 of the amended law of 8 April 2018 on public procurement): any invoice sent to a public sector body in the context of a contract concluded in writing therefore falls within the scope of the law and must be a compliant electronic invoice, regardless of the amount and type of procedure used to conclude the public contract. 

What is a public sector body? 

A body (government, municipalities, bodies governed by public law, associations formed by such authorities or bodies governed by public law, etc.) which, in the context of a public contract, purchases works, products or services or, put differently, any contracting authority or entity which falls within the scope of one of the laws referred to in Article 1 of the amended law of 16 May 2019 on electronic invoicing. 

Is an EIG (Economic Interest Group), some of whose members are public sector bodies, also affected by this new law? 

The law indicates:  

• Definition of "body governed by public law" in Art. 2(d) of the amended Public Procurement Act of 8 April 2018 as  

• "any body which has all of the following characteristics: 

1. it has been created specifically to meet needs in the general interest which are not of an industrial or commercial nature; 

1. it has legal personality; and 

1. it is financed by the State, the municipalities or other bodies governed by public law, or its management is subject to supervision by these authorities or bodies, or its administrative, management or supervisory body is composed of members more than half of whom are appointed by the State, the municipalities or other bodies governed by public law.” 

Examples: State, municipality, courts, union of municipalities, public law bodies, ministry, administration, judiciary, GIE, ASBL. This includes all bodies that are controlled or financed to more than 50% by the state. 

For economic operators: 

• issuing and transmitting compliant electronic invoices in the context of public procurement (Art. 4bis); 

• Using either the Peppol common delivery network or one of the authorized alternative non-automated technical solutions for this transmission. 

For public sector bodies: 

• receiving and processing compliant electronic invoices; 

• using, for the automated receipt of electronic invoices, the common delivery network Peppol and, if no own Peppol access point is available, the access point of the CTIE (Government IT Centre). 

For ministries and state administrations: 

• using the CTIE Peppol access point 

Note: This procedure also concerns credit notes and invoice cancellations 

What are the consequences by not respecting the regulations? 

For Public Sector bodies potentially: 

• intervention by the relevant Ministry; 

• infringement procedure launched by the European Commission against Luxembourg; 

• legal action by an economic operator. 

For economic operators: 

• potentially the non-payment of their bills; 

• invoice not issued in accordance with legal requirements; 

• since the creditor has not fulfilled his legal obligations, it is impossible to invoke late payment or interest for late payment (Art. 4, § 1 of the amended Act of 18 April 2004 on payment periods and interest for late payment). 

If the public sector body is not ready, how will they receive our invoices electronically? 

It is necessary to inform the Ministry of Digitalisation about the relative public sector body. The Ministry of Digitalisation is then able to contact this body and remind it of its obligation. Once the identifier has been obtained, the Ministry of Digitalisation can set it on the CTIE access point. 

The law provides for a staggered entry into force between 18 May 2022 and 18 March 2023, depending on the size of the companies concerned:

• to large economic operators, 5 months after the entry into force of the law, i.e. on 18 May 2022;
• medium-sized economic operators, 10 months after entry into force, i.e. on 18 October 2022;
• small and newly established economic operators, 15 months after entry into force, i.e. 18 March 2023.

Is there a date for B2B/B2C in terms of obligation?

No, but the new law aims to encourage businesses to invoice electronically.  
Beyond the legal requirements associated with B2G, electronic invoicing offers significant benefits ranging from operational efficiency and cost reduction to improving transaction traceability. This transition provides your company with the opportunity to streamline its administrative processes and enhance competitiveness in the market, both in the B2G sector and the B2B sector. 

Will the content format change in the next 5 years?

It is possible. But the changes will take place at the level of Peppol and its standards. This does not mean that companies must change the files they use internally

Large economic operators

Those exceeding, at the balance sheet of 2019, the numerical limits of at least 2 of the following 3 criteria:

• balance sheet total: €20 million;
• net turnover: €40 million;
• staff employed full time and on average during the year: 250.

Medium-sized economic operators

Those that do not exceed, at the balance sheet of 2019, the numerical limits of at least 2 of the following 3 criteria:

• balance sheet total: €20 million;
• net turnover: €40 million;
• staff employed full time and on average during the year: 250.

Small economic operators

Those that do not exceed, at the balance sheet of 2019, the numerical limits of at least 2 of the following 3 criteria:

• balance sheet total: € 4.4 million;
• net turnover: € 8.8 million;
• staff employed full time and on average during the year: 50.

If a company has no employees?

Two criteria define the date of application of the new law:

• balance sheet
• turnover

Should we consider the Luxembourg-based economic operator or the entire group?

The economic operator, who signs the contract, i.e. the one who appears on the invoice, has to be considered.

An economic operator has several options to transmit compliant electronic invoices via Peppol:

• rent a Peppol access point from one of the many specialized service providers already active in the field; and connect the accounting application to the access point
• set up their own Peppol access point, which is an option for organizations of a certain size and that have their own experienced and well-resourced IT department;
• use one of the invoicing or accounting software (ERP), which already integrate a Peppol subscription/connection.

What are the non-automated alternatives?

To meet the needs of economic operators, who do not yet have the capacity to issue and transmit electronic invoices automatically via Peppol, alternative non-automated technical solutions which only allow the manual and individual issue and transmission of electronic invoices are made available to economic operators.

Go to the online form on myGuichet to issue and send a compliant electronic invoice by manually entering the elements of the invoice in the form fields.

If you want to issue and send an electronic invoice by uploading an already compliant electronic invoice, please fill in this online form

New web forms for electronic invoicing "without authentication": Procedures for public institutions and economic operators 

Recently, both types of web forms for electronic invoicing on MyGuichet.lu, enabling economic operators (EOs) to submit their electronic invoices to public institutions (PIs), have been made available in a version that does not require electronic authentication of the EO: 

• guichet.public.lu/en/entreprises/commerce/marches-publics/facturation/emission-facture-electronique-marche-public-contrat-concession.html 

• guichet.public.lu/en/entreprises/commerce/marches-publics/facturation/transmission-facture-electronique-marche-public-contrat-concession.html 

These two versions without authentication have the advantage that an EO without any of the numerous electronic identification means (eIDs) accepted by MyGuichet (various LuxTrust tools, the Luxembourg electronic identity card, or any of the many foreign eIDs with high-security levels notified under the EU regulation eIDAS) can easily submit an e-invoice. 

However, these versions without authentication should only be used by EOs who objectively have no means of electronic authentication. The absence of authentication poses a series of disadvantages for both the EO and the PI: 

• No access for the EO to the automatic form pre-filling functions with data already stored in the professional space of MyGuichet. 

• No opportunity for the EO to copy an older invoice already submitted to the same recipient, saving time by using a pre-filled invoice. 

• No option for the EO to obtain the compliant e-invoice (XML file) generated after submitting the web form data or the representation in a human-readable PDF format of the essential data extracted from the compliant e-invoice. 

• Higher risk for the PI to receive "false" invoices from actors impersonating EOs. 

To largely mitigate the last of the disadvantages described above (the risk of receiving fake invoices from criminal actors), the following procedure has been introduced: 

• Before using such a web form for electronic invoicing without authentication, the EO must receive a voucher from its customer, i.e., the PI to which it wants to send the e-invoice - actually, a unique number that can only be used once - and must indicate this number on the first page of the web form without authentication to continue the process. 

• In a version without authentication, the EO must always download a purchase order or another document that establishes the contractual connection under which the invoice is issued. 

• This purchase order or another document must be provided by the respective PI to the concerned EO before issuing the invoice. 

• To distribute the above-mentioned vouchers (for single use), PIs must request them in advance or as needed via email to the address info@efact.public.lu of the Ministry of Digitalization's E-Invoicing team. 

• Upon request, a PI will receive a default list of 10 vouchers that it can gradually pass on to its EOs as needed. 

• Each voucher can only be used once; therefore, the PI must ensure not to distribute the same voucher twice and mark each already distributed voucher as invalid. 

• When all vouchers are used or nearly used, the PI can request new vouchers at info@efact.public.lu. 

• It is strongly recommended not to transmit vouchers simply via unsecured email but each time through a secure and encrypted channel (encrypted messaging, encrypted email, etc.) or directly by phone. 

Find here tutorials on guichet.lu on how issuing an electronic invoice :

See tutorial

If I use the solution on myguichet.lu, is there a possibility to save the information of the invoice?

There are the normal features, in the professional area. The information you enter in this area (email, organization, etc.) is by default used in the form. Normally, the form is pre-filled with your data.

Can public institutions benefit from the CTIE access point?

Yes, it is an obligation, for public sector organizations that have not yet implemented a solution in their structure.

Note: the sender and receiver must not be registered with the same provider

In the solution on myguichet.lu, the unit price is reduced to 2 decimal places. What do you do if your unit prices have 4 decimal places?

The Ministry of Digitalisation will analyze this issue in more detail. Peppol calculates rounding in a very specific way and it must be ensured that what is done in the online forms corresponds to what is done at Peppol level. They will probably allow in the future the unit price line to be 4 digits after the decimal point.

Which solution is the best: Peppol or Myguichet.lu? 

In general, the use of Peppol is always the preferred solution for businesses of any size that send a large number of invoices. Indeed, Peppol enables process automation, leading to higher efficiency. Meanwhile, alternative solutions on MyGuichet.lu are more suitable in the short term for businesses and other organizations that issue only a few invoices per month. 

Peppol is the common delivery network chosen to enable the automated issue, transmission, and receipt of electronic invoices. It is managed and maintained by the international non-profit association under Belgian law, OpenPeppol.

Peppol is designed as an open and interoperable network by default which allows any organization, once it has taken the necessary steps to have an access point to the network, to communicate automatically in both directions (sending and receiving) with any other member of the network without having to make any additional specific effort if it wants to send or receive files from a new member organization with which it did not have an exchange before.

The network is also secure by default, in particular through encryption of communications between two access points, and guarantees non-repudiation by default and uses an exchange format for electronic invoices that complies with the most recent version of the European standard on electronic invoicing.

How exactly does Peppol work?

Delivery network: a system for sending structured electronic documents between two access points in a secure manner.

There is a connection (corner 1) via an ERP, an invoicing software, an accounting software that sends the invoice. This back office must be connected to the Peppol network which sends the invoice (corner 2). The invoice is received (corner 3). Corner 3 sends the invoice back to the final recipient to his accounting software (ERP) (corner 4).

Peppol just covers corner 2 and 3 and the connection between the two. Peppol defines the standards, the criteria and the communication. The communication is done via internet, but it is encrypted and secure. What happens between the back offices and the access points must be defined by each organization itself. These connections can be made in different ways. Peppol can be used in the global network provided that the company has its Peppol ID. Peppol has a strong presence in Europe. The software does not create Peppol compliant invoices, it creates XML files which are then sent to an access point which takes care of the conversion of the XML files to the Peppol standard.

How can we find participants of the Peppol network?

Two Peppol directories allow to find network participants and their identifiers:

The SML directory for production environments and the SMK directory for test environments.

At the moment, it is not mandatory for network participants to publish their data in these directories. Therefore, not all organizations can be found there. However, all participants using the CTIE Peppol access point will be automatically published in these directories.

How to use the test environment in Peppol?

The test environment of the CTIE's Peppol access point is, like the production environment, in place since December 2016.

Any economic operator can send test messages to this server.

The ID to be used for addressing is:

• lu10889245-test or
• lu10889245 (CTIE VAT number) simply

Details can be found here.

What are the identifiers to be used in Peppol for addressing?

At the moment, the identifier to be used to issue an invoice is the VAT number of an organization.

In the future, a specific code-list, to be integrated in Peppol, will be proposed for the identity numbers of the register of legal persons.

Only identity numbers from the register of legal persons will be allowed (not before the second half of 2023).

• Codelist to be used, at present, in Peppol for the 2 types of numbers:
  9938, i.e. LU:VAT. The numbers are therefore of type :
• 9938:lu10061242 or
• 9938:12345678910

Is there an equivalent to the acknowledgement of receipt with Peppol?

The access point can send a confirmation that the invoice has been received.

Note: the sender and receiver must not be registered with the same provider

Where can I find Peppol access point providers?

You will find a list of certified Peppol providers, who help you with the rental of a Peppol access point.

Or you can contact an accredited provider from the SME Packages - Digital program, if you are interested in implementing an ERP in your company.

An open list of national service providers (PDF, 109 KB) and international service providers (PDF, 188 KB) in the context of invoicing has been compiled by the Chamber of Commerce and the Chamber of Crafts. Any service provider wishing to be highlighted on these lists should get in touch with the digital service of the House of Entrepreneurship and provide all the information specified in the table. 

What format should be used?

The European standard EN 16931 1 2017 +A 1 2019 (Edition 11 2019 defines the essential information elements that an electronic invoice must contain to comply with legislation (including tax legislation) and to ensure interoperability across sectors, countries and borders.

The second part CEN/TS 16931 2:2017 (Edition 06/2017) lists the approved syntaxes / languages:

• XML UBL (Universal Business Language) defined in ISO/IEC 19845:2015 and maintained by the non-profit organisation OASIS Open;
• UN/CEFACT CII (Cross Industry Invoice) XML developed by UN/CEFACT, as specified in XML Schema 16B (SCRDM - CII).

/!\ The UBL format should be preferred. The use of the UN/CEFACT CII format may not be supported by a large number of access points.

What are the specifications of the Peppol BIS Billing 3.0 standard?

The standard electronic invoice used in Peppol is Peppol BIS Billing 3.0 in XML UBL format. All details regarding this standard can be found here: https://docs.peppol.eu/poacc/billing/3.0 

This standard is the only one that all Peppol access points must receive and process. Therefore, it is strongly recommended to always use this standard for sending invoices. 

Other types of electronic invoices that comply with legal requirements (XRechnung 2.2 in UBL and CII format, Peppol BIS Billing 3.0 in CII format, Peppol EN 16931 UBL invoice, etc.) can also be exchanged over the Peppol network. However, these are formats that are either used nationally or are rarely or minimally used in practice. Many or even most Peppol access points are often unable to receive these formats. Therefore, it is generally discouraged to use these formats. 

How do I get a Global Location Number (GLN) for Peppol?

You don't need the GLN for Peppol, you just need a Peppol ID (with the registration number or the VAT number) and have a service provider who will set you up on an access point.

Is the “XML-Xrechnung” format generated as standard by ERPs accepted by the state and Peppol?

For an XRechnung, it is essential to add the Peppol identifiers of the sender and the recipient in the XML file as follows (as they are not automatically specified in this format): 

• For a UBL-type XML file, the identifiers of the sender (cac:AccountingSupplierParty) and the recipient (cac:AccountingCustomerParty) must be provided, for example: 

<cbc:EndpointID schemeID="9938">LU31168204</cbc:EndpointID> 
 

• For a UN/CEFACT CII-type XML file, the identifiers of the sender (ram:SellerTradeParty) and the recipient (ram:BuyerTradeParty) must be provided, for example: 

<ram:URIUniversalCommunication> 
<ram:URIID schemeID="9938">LU31168204</ram:URIID> 
</ram:URIUniversalCommunication> 
 

The schemeID to be used for all Luxembourg organizations in the public and private sectors is "9938." For other countries, the schemeID prescribed in the Peppol network for that country must be used

How to validate the conformity of an XML file?

You can have the conformity of your XML file validated on Schematron or on the web page dedicated to the validation of XML files.

Can XML invoices be sent by e-mail?

No

Will only the XML file of the invoice be transmitted or with the PDF attached?

Only the XML file must be transmitted, but attachments can also be transmitted.

Does the XML file under this law meet the VAT requirements to avoid non-deductibility concerns?

The VAT aspect is currently not covered in this directive. The standard, that is used at Peppol level, is in line with the European standard: EN 16931 1. There is no direct link for the moment with the legislation and what is done at the VAT level.

This year there will be a new proposal for a new VAT directive.

Who is responsible when invoices go through intermediaries to validate payment?

Anything that happens before or after the invoice is sent is not the responsibility of Peppol. The procedures can be done as usual.

How are the 'non-accounting' criteria of an invoice handled? For example: retention of guarantee.

The Peppol format contains many fields. Everyone can contact their own Peppol provider.
 

How can foreign economic operators invoice electronically? 

Foreign economic operators have the same channels available for submitting compliant electronic invoices as national economic operators. These transmission channels are default open, cross-border, non-discriminatory towards foreign economic operators, and can therefore be easily utilized by them. The following options are available: 

• For automated and efficient transmission of compliant electronic invoices, the international and cross-border delivery network Peppol (peppol.org) can be used. 

• For manual transmission of compliant electronic invoices, the two types of web forms on MyGuichet.lu are available. 

Here are the links to the two types of web forms on MyGuichet.lu: 

• Manual entry of an electronic invoice in the context of a public tender or concession contract. 

• Transmission of an already compliant electronic invoice in the context of a public tender or concession contract. 

These web forms are available in versions: 

• With authentication, enabling the use of around 15 different eIDs (electronic authentication means) from other European countries. 

• Without authentication, specifically intended for economic operators who either do not yet have an eID or do not possess any of the many foreign eIDs accepted on MyGuichet.lu. 

Those wishing to use the versions without authentication of the forms must request the public institution of the sector to which they intend to send the invoice to provide them with a unique code, which they must specify on the first page of the form. Before submitting their invoice to the invoice recipient, they must also download a purchase order or another document representing the contractual connection, which was previously provided to the economic operator by the respective public institution of the sector. 

Project VAT in the Digital Age (ViDA), what is it about? 

The ViDA reforms aim to simplify value-added tax rules for cross-border electronic commerce and create fair competition conditions for businesses in the EU and third countries, ensuring that value-added tax is paid where consumption takes place. 

At the current stage, ViDA is only a proposal. It must be unanimously adopted by all member states. The timeline is uncertain, and there are differing opinions among various EU member states on different aspects of the proposal. 

Sending of invoices:

As of 18 May 2022, invoices sent to public sector bodies, ministries or state administrations must be sent exclusively in the electronic format provided for by the law, using the PEPPOL network (via the CTIE access point for the Luxembourg state). The encoding of the invoices in question will always be done by the person concerned in our ERP (SAP). The invoices will be sent to the customer by the accounting department via the PEPPOL network. We would be grateful if you could refrain from sending invoices to public sector bodies, ministries or government departments by PDF or post.

Receipt of invoices:

As regards the receipt of invoices, the Chamber of Commerce has been connected to the PEPPOL network since 18 May 2022 and electronic invoices are automatically redirected to the accounting department. In this context, it is important to transfer the Chamber of Commerce's PEPPOL identifier: 9938:lu15427942 to the suppliers beforehand.

Depending on the granularity required by the company's accounting department, we advise you to ask the suppliers to attach a pdf invoice to the electronic invoice (XML) to carry out a visual check and to obtain any additional information. For the time being, the Chamber of Commerce still accepts invoices in paper format or in PDF format.

If you have any questions about this information, please contact the accounting department.

The Chamber of Commerce, the Ministry of Digitalisation and the Chamber of Craft have set up a Helpline dedicated to invoicing issues: 

Tel: (+352)  247 72 155