Electronic logbooks become mandatory in payroll audits from 2027

The Digitale LohnSchnittstelle (DLS) is the standard record set for exporting data from the employer's payroll system and the upstream and downstream systems used for payroll to the auditor in a Lohnsteuer-AußenprüfungBzst. It fixes file and field structures independently of the payroll software in use, and the employer must hand the data to the auditor following DLS conventions. For wage data, DLS-Lohn applies to data recorded from 1 January 2018. For electronic logbooks, the DLS-Fahrtenbuch now becomes binding for data recorded in the Lohnkonto from 1 January 2027BzstBzst. The published package for that reporting year is version 2027.1Bzst, released with the news entry of 3 November 2026Bzst, replacing version 2026.1Bzst.

Logbook material is organised in seven data groups: FB_Programminfo with general system information, FB_Firmenstammdaten defining the lohnsteuerliche Betriebsstätte and the driver's allocation to the business, FB_Fahrerstammdaten with the driver's personal data and tax bases, FB_Fahrzeugstammdaten with vehicle data and its tax bases, FB_Bewegungsdaten with all trip information, FB_Fahrzeugkosten with vehicle costs, and FB_Tankdaten with fuel purchases and consumption. The primary keys are FB_Fahrer_ID and/or FB_Pers_Nr together with FB_FIN. For each year of the audit period a separate data set including the XML and dtd files must be delivered; the field order within each data group is mandatory while no record sort order is prescribed. The default encoding is UTF8 for index.xml and Windows ANSI for the data files, with any deviation declared in index.xml. The sample XML shipped with the package is an example only and must always be adapted to the data actually delivered; the current Datensatzbeschreibung governs.

Several conventions decide whether a delivery passes. Primary keys may each be assigned only once per calendar year, and the same Personalnummer must not be given to two different employees in the same year, while one employee may carry several Personalnummern. Numeric fields with value zero are shown as digits, empty numeric and character fields as blank, and empty date fields as 00.00.0000. A separate data set is required for each lohnsteuerliche Betriebsstätte under audit, for example individual group companies. Delivery covers, in every data group, all records for trips whose start or end falls in the audit period, with each audit year's files in a separately labelled subdirectory. Changes in movement data must not overwrite the original records: they go in a new complete record carrying the unchanged fields, flagged with the FB_Aend_Dat and FB_Aend_Zeit timestamps. Driver master-data changes take a further record with FB_Guelt_Dat. Combined trips need one additional complete record for the combined trip, with FB_Fahrt_ID_zus_Fahrt entered in the records of the trips combined, following Pkt. 11 of the package.

Two practical points round off the picture. The finance administration offers no test facilities for sample data, and a new DLS version is published for the coming year by 31 October each year; technical questions go to the Bund/Länder working group AG PSW LStAP at dls@bzst.bund.de. The broader access right to audit-relevant tax data remains unaffected. For employers with company cars, logbook data recorded from January 2027 must therefore follow the 2027.1 structure, regardless of the payroll software usedBzst.

The binding use of this standard record set was introduced by the Gesetz zur Modernisierung des Besteuerungsverfahrens of 18 July 2016 (BGBl. I S. 1679), as communicated in the BMF-Schreiben of 26 May 2017 (GZ IV C 5 - S 2386/07/0005 :001). The legal basis is § 4 Abs. 2a and § 8 Abs. 3 Lohnsteuer-Durchführungsverordnung together with § 147 Abs. 6 ff. AbgabenordnungGesetze IM Internet.