DATEV ASCII interface
Also: DATEV format · DATEV CSV · posting batch · EXTF
The DATEV format is a standardised file format for exchanging accounting and master data with DATEV financial accounting. It is widely used to hand data from upstream systems such as merchandise management, invoicing or point-of-sale over to the accounts.
What it is
The historically common term "DATEV ASCII interface" today usually refers in practice to the DATEV format with CSV-based exchange files. The format covers not only posting batches but also further data types such as customer and supplier master data or general ledger account descriptions.
In a posting batch the first line holds a defined header. Among other things it contains the format identifier and version, the adviser and client number, the start of the financial year, the general ledger account length and the period covered by the batch.
The following lines contain the posting data. The central fields include the amount, the debit/credit indicator, account, contra account and document date. Further fields such as the tax key, document reference fields, posting text, cost centres or service date are used depending on the transaction concerned.
What is transferred is therefore not the original PDF or paper documents but structured posting and master data. Which accounts, tax keys and additional details are used has to be established in the upstream system or in the processing ahead of it.
In practice
The DATEV format is strictly specified. Header, field order, number and date formats, field lengths and character encoding all have to follow the specification. The general ledger account length stated in the header, for example, must match the client's configuration.
Character encoding matters too: DATEV supports different encodings, and additional rules apply to Unicode depending on the import route. A file should therefore not only be generated with the right content but also validated formally before handover.
The more important question is the account determination. Which transaction is posted to which account, which tax key is required, and which cost centre should be used? These rules are established together with the accounting department or tax advisers and then implemented technically.
With automated handovers it should also be traceable which batches have already been generated and handed over. That prevents the same data being processed more than once unintentionally.
When it affects you
The DATEV format is relevant when posting or master data from an upstream system is to be transferred into DATEV financial accounting. That can involve exchanging data with a tax practice, but equally an in-house accounting department using DATEV.
The benefit grows with the volume and regularity of transactions. What is decisive, though, is not the number of documents alone but how unambiguously the posting logic can be derived from the existing business data.
For an initial assessment, a typical period from the upstream system, the desired DATEV target structure and the accounting rules are usually enough. From those it becomes clear which data can be transferred directly and where mappings or rules are still missing.