The authenticity of the origin, the integrity of the content and the readability of an invoice must always be guaranteed from the moment it is issued till the end of the period during which it should be kept in the records. The rules on this subject remain unchanged.
Issuing electronic invoices is only authorised till 31 December 2025 if the recipient of the invoice gives their express or tacit acceptance in this regard. As from 1 January 2026, this condition will no longer apply and sending and receiving will be compulsory.
Any document that makes changes to an invoice and refers specifically and unambiguously to the original invoice is considered as an electronic invoice and is issued in the same format as the original invoice.
If each party adequately guarantees these conditions, the true nature of the invoice will be clearer than in the past, when only the original invoice was taken into account as the starting point for VAT regulation. This applies to the retention of invoices, the exercise of the right to deduct and checks on compliance.
What is the “authenticity of origin” of the invoice?
“Authenticity of origin” means: “assurance of the identity of the person who supplied the goods or provided services or the person who issued the invoice.
Guaranteeing this authenticity is an obligation both for the person liable to tax receiving the supply of goods or providing services and for the person liable to tax making the supply or providing the services. Regardless of each other, both can guarantee the authenticity of the origin.
What is the “integrity of the content” of the invoice?
“Integrity of the content” means that the content of the invoice has not been changed in any way. As a general rule, this content corresponds to the one defined in the VAT Directive.
What is the “legibility of the invoice”?
“Legibility of an invoice" means that the invoice must remain legible till the end of its retention period. VAT data must be clearly legible, without an excessive examination or interpretation being needed.
For electronic invoices, the condition is met if the invoice can be presented on request. This must be done within a reasonable timeframe and in a format that can be read by the user. It must be possible to check whether the data of the original electronic file and the data of the readable document submitted correspond. To ensure that electronic invoices are legible, a suitable and reliable device allowing to view the invoice must be available for the entire retention period.
When is an audit trail reliable?
An audit trail is reliable when three conditions are met:
- the link between the supporting documents and the transactions processed is easy to follow (when the level of detail is sufficient to link the documents together);
- it complies with the applicable procedures;
- it corresponds to processes that have actually taken place.
This can be achieved, for example, with :
- documents drawn up by third parties (such as bank statements);
- documents drawn up by the purchaser/lessee or supplier/service provider (documents of the second part);
- internal controls (e.g. segregation of duties).
For VAT purposes, an audit trail must provide a link which can be checked between an invoice and a supply of goods or a provision of services (Art. 233, § 1, paragraph 2 of the VAT Directive). This makes it possible to check whether the invoice relates to the supply of goods or the provision of services which has been carried out.
The person liable to tax is free to choose how to dhow the link between an invoice and a supply of goods or a provision of services.
