Terms of use for Baden-Württemberg’s Central Invoice Submission Portal (ZRE)

1. Scope of the terms of use

As the operator of Baden-Württemberg’s Central Invoice Submission Portal (ZRE), the state of Baden-Württemberg (hereafter: ‘the operator’), via the technical services provider IT Baden-Württemberg (BITBW), provides invoice issuers and invoice senders (hereafter: ‘users’) with a service provided over the internet – the ZRE. The ZRE makes it possible for users to transmit electronic invoices (‘e-invoices’) to the invoice recipient.

The following terms of use apply to all services offered to users as part of the ZRE.

2. Definitions

The definitions in the state government’s directive on electronic invoicing in public procurement in Baden-Württemberg (Baden-Württemberg E-Invoicing Directive – ERechVOBW), dated 10 March 2020, apply, in particular the definitions of ‘invoice’, ‘electronic invoice’, ‘invoice issuer’, ‘invoice recipient’ and ‘invoice sender’. The ERechVOBW governs the arrangements for electronic invoicing in the state of Baden-Württemberg.

You can read the ERechVOBW (in German) online at http://www.landesrecht-bw.de.

3. Information on the responsible bodies

a) Operator of the ZREE

State of Baden-Württemberg Ministry of the Interior, Digitalisation and Migration

Willy-Brandt-Straße 41

70173 Stuttgart, Germany

Telephone:  +49 (0)711 / 231-4 

Email:  poststelle@im.bwl.de 

b) Technical services provider

IT Baden-Württemberg (BITBW)

Krailenshaldenstraße 44

70469 Stuttgart, Germany

Telephone: +49 (0)711 / 8910-40

Email: Poststelle@bitbw.bwl.de

c) Responsible Data Protection Officer

State of Baden-Württemberg Ministry of the Interior, Digitalisation and Migration

Official Data Protection Officer

Willy-Brandt-Straße 41

70173 Stuttgart, Germany

Email: Datenschutzbeauftragte@im.bwl.de

4. Subject and scope of the agreement

The services provided by the ZRE enable users to transmit electronic invoices, including any supporting documents, to the invoice recipient. The ZRE enables electronic invoices to be submitted by uploading them, emailing them or, at a later date, submitting them via the Pan-European Public Procurement OnLine (PEPPOL) web service infrastructure. The electronic invoices submitted through this service, along with any supporting documents submitted with them, are validated by the ZRE. The validation process comprises an inspection to ensure submitted documents comply with formal standards (for example: permitted invoice format and size limits, that all compulsory fields have been filled in and that any supporting documents referenced in the invoice are available – see the further explanations under point 5), along with a virus scan. Electronic invoices will not be accepted if they do not comply with formal standards or if malicious software is detected in them. After successful validation, electronic invoices are supplied to the invoice recipient for subsequent verification and processing. Users are notified that the invoice recipient has received the electronic invoice.

5. Permitted formats and size limits

a) Format for electronic invoices

The permitted invoice formats are those stated in Section 4 of the ERechVOBW. Electronic invoices must comply with the XRechnung data exchange standard dated 10 July 2019 (BAnz AT 31.7.2019 B1) in its currently applicable version. Other data exchange standards can be used, provided they meet the requirements of the European Standard for Electronic Invoicing, in accordance with Article 3 of Directive 2014/55/EU of the European Parliament and the Council of 16 April 2014 governing electronic invoicing for public contracts (Official Journal L 133 dated 6 May 2014, page 1).

The XRechnung data exchange standard was developed by the Coordination Centre for IT Standards, on behalf of the IT Planning Council. The latest version of the XRechnung data exchange standard can be found on the website of the Coordination Centre for IT Standards (KoSIT) (in German).
The European standard for electronic invoicing EN 16931-1-2017 was published by the European Committee for Standardization (CEN) on 28 June 2017.

The electronic invoices submitted are inspected for compliance with the standards of the XRechnung data exchange standard and European standard EN16931-1 by means of schema/schematron verification processes which meet the respective standards.

Furthermore, in accordance with Sections 5 and 6, Paragraph 3 of the ERechVOBW, electronic invoices must contain the following compulsory information required by XRechnung or EN16931-1:

Compulsory information in accordance with Sections 5 and 6, Paragraph 3 of the ERechVOBW Fields in XRechnung or EN 16931-1
The invoice recipient’s buyer reference* BT-10
The user’s bank account data For electronic transfers:
BG-17 (BT-84 to BT-86)
For direct debit**:
BG-19 (BT-89 to 91)
Payment terms BT-20 and/or BT-9
The user’s email address BT-43
Supplier number (if known) BT-29
Order number (if known) BT-13

BT = Business Term or information element
BG = Business Group or group of information elements
* The invoice recipient provides the invoice issuer with the buyer reference when ordering the product(s) or service(s).
** Only where a SEPA direct debit mandate has already been issued.

b) Format for any supporting documents for the electronic invoices, plus size limits for electronic invoices and supporting documents

For format specifications for supporting documents supplied with electronic invoices and size limits for electronic invoices and supporting documents, see the appendix ‘Technical information’.

It is possible to embed any supporting documents into the invoice document, or to reference them as separate downloadable resources by means of a link/URL. Successful submission depends on all attachments referenced by means of a link/URL being available at the time of submission. The file formats of the invoice’s supporting documents should be agreed with the invoice recipient in advance. Otherwise, if the invoice recipient cannot open the attachments, the invoice will be returned.

Complying with the specifications listed under point 5 is a prerequisite for ensuring the ZRE can prepare the electronic invoice so it can be collected by the invoice recipient.

6. Technical conditions that are the responsibility of the user

For further technical conditions that the user must fulfil in order to use the ZRE’s services, please see the appendix ‘Technical information’.

7. Receipt of electronic invoices

Electronic invoices are considered to have been received by the invoice recipient as soon as the ZRE has determined that they have been submitted correctly. This is the case when invoices have been received by the ZRE and have successfully passed the inspections described. The prerequisite for this is that the requirements for electronic invoices and their supporting documents, in respect of their format and size limits, have been fulfilled. Users receive a notification stating that the invoice has been successfully submitted. Depending how they submitted the invoice, this will be in the form of a status notification in their web browser, or an email. Users can view the status of an electronic invoice submitted via the ZRE at any time by visiting the status page for the uploaded invoice in the ZRE’s web interface. Log data is deleted 30 days after the last status change.

8. Usage times

The ZRE’s services are available to users from Monday to Sunday, between 00:00 and 23:59. However, as a result of maintenance work sometimes carried out between 17:00 and 08:00, response times can sometimes be longer or the service can sometimes be unavailable for short periods. In urgent cases, the above-mentioned restrictions and limitations may also occur if special maintenance has to be undertaken outside these times.

9. Support

Users with technical and functional queries can contact service-bw’s support. To do so, email service-bw@im.bwl.de.

10. Costs

Use of the ZRE is free of charge for users. However, the user’s costs in relation to using the ZRE, in particular for the provision, connection and operation of any necessary software and hardware, and for the internet connection, will not be refunded by those responsible for the ZRE.

11. Data protection

The data protection declaration for use of service-bw, and therefore also the ZRE, is available at the following link: Data protection declaration for service-bw – Service Portal Baden-Württemberg

12. Due diligence obligations

a) Responsibilities for determining protection requirements

The ZRE takes into account the need to protect the personal data contained in the electronic invoices.

However, invoices which, according to Section 4, Paragraph 2, points 1 to 4 of the State Security Review Act, contain data which must be kept confidential, and which are therefore excluded from the scope of the ERechVOBW, as set out in Section 1, Paragraph 2 of the ERechVOBW, must not be submitted via the ZRE. Users are responsible for complying with this requirement.

b) Scanning for malicious software

Before transmitting any files, users are obliged to check that files do not contain malicious software. Only files which do not contain malicious software should be sent via the ZRE. If any electronic invoices submitted are found to contain malicious software, the submission process will be blocked. If the invoices are submitted by email, the user does not receive any notification that this has occurred.

13. No guarantee; Exclusion of liability

a) No guarantee

The operator does not guarantee that the ZRE’s services will be available at all times. However, the operator strives to ensure that submitted, validated electronic invoices are made available for collection by the invoice recipient specified by the buyer reference as soon as possible.

b) Exclusion of liability

  1. All user claims for damages are excluded. Exceptions to this are user claims for damages resulting from loss of life, bodily injury or harm to health or the significant breach of essential contractual obligations (cardinal obligations), as well as liability for other damages resulting from wilful or grossly negligent breach of duty by the operator, its legal representatives or agents. Essential contractual obligations are those which are necessary in order to fulfil or achieve the contract’s objective.
  2. In the event of an ordinary breach of essential contractual obligations, the operator is only liable for foreseeable damages typical of the contract, unless the user’s claim for damages results from loss of life, bodily injury or harm to health.
  3. The limitations set out in paragraphs i) and ii) also apply in favour of the operator’s legal representatives and agents if the claims are directly made against these.

c) Legal requirements for invoices

The operator cannot be held liable for ensuring that electronic invoices submitted via the ZRE meet all legal and tax law-related requirements. This is the user’s responsibility. Furthermore, the operator is also not responsible for adhering to the data retention periods required by commercial and tax law.

14. Closing provisions

  • The laws of the Federal Republic of Germany and the state of Baden Württemberg apply, with the exception of the provisions of international private law.
  • The place of fulfilment for all services is Stuttgart. The place of jurisdiction for all disputes arising from this contract is Stuttgart. The operator reserves the right to take proceedings against the user at any other competent court of law. This jurisdiction clause only applies when the user is a trader, legal entity under public law or a special fund under public law.
  • In the event that individual provisions of these terms of use are found to be invalid, or become invalid, either in whole or in part, the validity of the remaining provisions remains unaffected. The provision(s) found to be invalid, either in whole or in part, will be replaced by a provision or provisions whose effect is as close as possible to the objective of the provision(s) found to be invalid.
  • The operator reserves the right to amend these terms of use, with future effect. Any such changes to the terms of use will be published at https://service-bw.de/erechnung.


Technical information

1. Size limits


There are limitations in respect of invoice documents and any supplementary documents embedded in it or referenced by it in links/URLs. These limitations apply to the number of documents, as well as their size.

An electronic invoice, including any supporting documents embedded in it or linked from it, must not exceed the maximum permitted file size of a total of 15 megabytes. The maximum number of an invoice’s supporting documents is limited to 100.


When submitting electronic invoices via email, please note that any text entered into the email, and any attachments which do not meet the requirements for permitted electronic invoice formats, will not be considered. This can lead to the submission being denied.

Attention: For data protection reasons, only exactly one invoice can be submitted in any single email. If an incoming email contains more than one invoice, submission must be denied.

2. Permitted formats for invoices’ supporting documents

The following file formats can be embedded into an electronic invoice as supporting documents:

  • PDF files
  • Images (PNG, JPEG)
  • Text files (CSV)
  • Excel spreadsheets (XLSX)
  • OpenDocument spreadsheets (ODS)

Only the HTTP and HTTPS protocols are supported for referenced supporting documents.

3. Technical conditions that are the responsibility of the user

To use the ZRE, users require an internet connection and software and hardware for displaying websites or sending emails.


The web interface for submitting electronic invoices by uploading them has been designed for use on desktop/laptop computers.


The web interface for submitting electronic invoices by uploading them is responsive, and therefore adapts to the characteristics of the respective device being used. It has been designed to display properly in commonly used browsers in their respective current versions.

Web service via PEPPOL

To use the ZRE via the PEPPOL web service, users require an internet connection plus hardware and software that meets the interface specifications.

Display of invoice fields in invoice processing systems

It cannot be guaranteed that all invoice fields will be shown with the same field lengths in the systems the invoice recipient uses to process the invoices.