DSFinV-K 3.0: New requirements for point-of-sale systems – what businesses need to know now

What you can expect from this article

In a letter dated 26 October 2026, the Federal Ministry of Finance revised the application circular relating to Section 146a of the German Fiscal Code (AO). This is primarily due to the introduction of version 3.0 of the Tax Administration’s Digital Interface for Point-of-Sale Systems (DSFinV-K). These new administrative regulations will, in principle, apply from 1 January 2029. Nevertheless, businesses should address the implications for their cash management and cash register documentation at an early stage.

The till must comply with legal requirements

Electronic point-of-sale systems are part of day-to-day operations in many businesses. Whether in the retail sector, the hospitality industry or the service sector, the till is used to record turnover, document payments and generate data relevant for tax purposes. It is not enough for a point-of-sale system simply to function reliably in day-to-day operations. Furthermore, the recorded data must also comply with legal requirements and be available in a verifiable format in the event of a tax audit.

The DSFinV-K 3.0 further develops the technical specifications for the standardised export of POS data. At the same time, the tax authorities are updating their guidance notes. But what does this mean in practical terms for businesses? Are there any recommendations for those responsible? What deadlines apply? And why should procedural documentation not be overlooked during a transition?

What is the DSFinV-K?

The abbreviation DSFinV-K stands for „Digital Interface of the Tax Authorities for Point-of-Sale Systems“. It defines a standardised format in which tax-relevant data from certain electronic point-of-sale systems must be made available for audit purposes. The aim is to establish a uniform and machine-readable data structure. This is intended to enable the tax authorities to efficiently examine POS data as part of an external audit or a POS inspection.

Important: The DSFinV-K must be distinguished from the technical security device (TSE). Whilst the TSE serves to safeguard electronic records, the DSFinV-K regulates the structured provision of certain till data. Both components fulfil different functions, but complement one another in ensuring the traceability and verifiability of electronic till records.

What changes did the Federal Ministry of Finance (BMF) make on 26 October 2026?

In a letter dated 26 October 2026 (Ref. IV D 2 – S 0316-a/00027/009/024), the Federal Ministry of Finance revised the Application Circular to the Tax Code relating to Section 146a. The main reason for this is the revision of the DSFinV-K to version 3.0. The Application Circular on the German Fiscal Code (AEAO) contains administrative instructions on the application of tax law provisions. It thus clarifies the tax authorities’ position, but does not replace either the statutory provisions of the Tax Code or the Cash Register Security Regulation. The revised version is intended to adapt the administrative regulations to the further developed technical interface requirements.

Important: The BMF letter does not introduce a general obligation to convert all electronic cash register systems to DSFinV-K 3.0 as early as October 2026.

What is crucial, rather, is the standard start date for implementation and the specific provisions governing earlier use of the new interface version.

When does DSFinV-K 3.0 come into force?

As a general rule, the following applies to the revised version of the AEAO relating to Section 146a of the AO: 1 January 2029 as the start date for the application.

However, the BMF letter contains an important provision: if the DSFinV-K 3.0 is applied before 1 January 2029, the revised application circular on Section 146a of the German Fiscal Code (AO) must also be applied earlier accordingly. In this regard, the letter refers to paragraph 5 of DSFinV-K 3.0.

For businesses, this means that it is not just the calendar date that matters, but also the version of the interface actually in use. Anyone upgrading their till system to the new version ahead of schedule should therefore ensure that the associated administrative requirements are taken into account.

The technical changeover should be coordinated with the till manufacturer or software provider.

Why is the DSFinV-K important for tax audits?

In the event of a tax audit or a cash register inspection, the tax authorities may require the provision of electronic cash register data. This data must be complete, traceable and available in the prescribed format. A functioning cash register interface alone is not sufficient for this purpose. It must also be possible to properly record and provide the business transactions, cancellations, payment methods and other information relevant to the audit that is stored in the background.

The following are therefore of particular importance:

• the complete, itemised record of business transactions,
• proper protection by a certified TSE,
• the storage of electronic till data,
• the provision of the necessary data exports,
• the traceability of changes and cancellations, as well as
• documentation of the systems and organisational processes in use.

Incorrect or unavailable till data can give rise to significant tax risks. If statutory record-keeping and disclosure obligations are breached, this may – subject to the relevant legal conditions – have implications for, amongst other things, the evidential value of the accounts and the tax authorities’ power to make assessments. It is therefore advisable to carry out regular checks on POS systems and their export functions – regardless of whether a tax audit has already been announced.

DSFinV-K 3.0 and GoBD: Why process documentation must be taken into account

When introducing new technical requirements, companies often focus on the software.

• Is the update being installed?
• Is the interface working?
• Can the data be exported?

However, at least as important is the question of whether the actual processes within the company are adequately documented. This is because the principles governing the proper management and retention of books, records and documents in electronic form, as well as data access – known as GoBD for short – require traceable documentation of the relevant organisational and technical procedures.

Procedural documentation is intended, in particular, to explain how tax-relevant information is generated, processed, stored and retained. In the case of electronic point-of-sale systems, for example, this concerns the hardware and software used, areas of responsibility, operating procedures, cancellation processes, data backups and the provision of data for audit purposes.

If a till system is updated or its technical interface is changed, it may therefore be necessary to amend the existing procedural documentation. This depends on the actual impact of the change. Not every software update automatically leads to a comprehensive revision of the entire documentation.

It is crucial that the documented processes continue to correspond to the systems and procedures actually in use.

What, specifically, should companies be looking into at this stage?

Although the new administrative regulations will, in principle, not come into force until 2029, those responsible should not put off their preparations until just before the deadline. Instead, companies can lay the groundwork today.

1. Record the point-of-sale systems in use

What electronic recording systems are used? Which software versions are installed? And what technical security measures are in place? An up-to-date system overview will make the subsequent transition easier.

2. Contact your health insurance provider

Organisations should clarify at an early stage when their provider will support DSFinV-K 3.0 and whether early adoption is planned. They should also clarify what technical and organisational changes will be required.

3. Check data exports

Can the required till data be provided in a complete and machine-readable format? This question is not only relevant in the context of DSFinV-K 3.0, but is already an integral part of proper electronic till management today.

4. Update the procedural documentation

Are the POS systems in use, responsibilities, control measures and procedures described fully and accurately? The documentation should be reviewed, particularly following system changes or major updates.

5. Document changes in a way that is easy to follow

When migrating to DSFinV-K 3.0, it is important to record when each change was made, which systems were affected and how the correct provision of POS data was verified. This will enable it to be traced at a later date which technical and organisational conditions were in place at a specific point in time.

Cash register report pursuant to Section 146a of the German Fiscal Code (AO): Not to be confused with the DSFinV-K

In the context of electronic cash register systems, the obligation to provide information under section 146a(4) of the German Fiscal Code (AO) is also frequently discussed. However, this must be distinguished from the DSFinV-K. This is because the DSFinV-K concerns the standardised export of cash register data for tax audits. By contrast, the cash register report serves to transmit specific information via electronic recording systems to the tax authorities.

The electronic notification procedure has been available for this purpose since 1 January 2025. For newly acquired or decommissioned systems subject to notification, a notification period of one month generally applies. The revised version of the application decree for DSFinV-K 3.0 does not automatically give rise to a new, separate reporting obligation. Companies should therefore consider both requirements separately and take them into account accordingly in their internal processes.

Cash register documentation with Opti.Tax: Recording processes in a traceable manner

Proper cash register management involves more than just technical interfaces and legally required records. Documenting the underlying processes also plays an important role. Here, businesses can use the Opti.Tax software solution to create and maintain their cash register documentation in a structured manner. In particular, the tool facilitates the clear and traceable description of the systems used, organisational responsibilities and tax-relevant procedures.

Particularly when technical changes occur, such as the introduction of a new version of DSFinV-K, it is helpful to be able to review and update existing documentation in a targeted manner. Opti.Tax supports the documentation of these procedures. The technical implementation of the DSFinV-K, as well as the provision of the required POS data exports, remain the responsibility of the respective POS systems in use and their suppliers. This allows technical requirements and organisational documentation obligations to be effectively combined.

If you have any further questions, please do not hesitate to get in touch. We look forward to hearing from you.