Social insurance registration for newly arrived employees in Germany: immediate report, insurance number, tax ID

Under section 28a SGB IV an employer registers a new employee with the first payroll run that follows, and at the latest within six weeks of the start of employment. In the sectors listed in section 2a of the Undeclared Work Act (SchwarzArbG) an immediate report is due as well: it has to reach the data centre of the German Pension Insurance no later than the day work begins.

Two deadlines, two different reports

The two reports are often confused, although they go to different recipients and run on different clocks.

The registration under section 28a(1) SGB IV goes to the employee's health insurance fund as the collecting body. It carries the start of employment, the contribution group key, the insurance number and the type of employment, meaning insurable employment, mini job or short term employment. It is filed electronically from the payroll software under the data collection and transmission regulation (DEÜV); the German Pension Insurance describes the procedure in its summa summarum guidance.

The immediate report under section 28a(4) SGB IV goes to the data centre of the pension insurance and carries only basic personal details and the first day of work. It does not replace the ordinary registration; it comes on top of it. The sectors concerned are those named in section 2a SchwarzArbG, among them construction, hospitality and accommodation, and the forwarding, transport and logistics trade. In those sectors a person who starts on Monday is reported on Monday, not with next month's payroll.

The bottleneck for newly arrived staff: two missing numbers

For a worker entering Germany for the first time, two items the reporting procedure normally assumes are not yet there.

The insurance number does not exist. The health insurance fund triggers it on the basis of the registration and the German Pension Insurance issues it. The employer therefore files without an insurance number and transmits the personal details instead: name, date of birth, place of birth, birth name, nationality and address. The number comes back afterwards and is carried in later reports. An empty field is not a reason to let the deadline run out.

The tax identification number follows a different route. The Federal Central Tax Office issues it after the person has registered with the residents registration office, and it arrives by post at the registered address. Until it is there, the employer runs payroll under the rules for a missing identification number, which in practice means a less favourable wage tax class and a correction in the following month. Registration with the residents office requires a residential address, so where the employer provides the housing, the tax ID hangs on the tenancy agreement or the landlord confirmation. The requirements for that housing are set out in worker accommodation and employer obligations.

The failure looks like this in practice. A logistics company hires four warehouse workers from Nepal on 2 March, with their appointment at the residents registration office booked for 10 March. Payroll waits for the registration confirmation and the tax ID, and holds back the immediate report as well. An inspection on 5 March finds four people on the floor with no immediate report filed. The immediate report depends on neither the insurance number nor the tax ID; it could have gone out on 2 March using the details in the passports.

What customs sees at the place of work

In the sectors covered by section 2a SchwarzArbG an identity duty runs alongside the immediate report. Employees have to carry an identity card, passport, passport substitute or identity substitute while working and produce it to the customs inspectors of the undeclared work unit on request (Zoll, 2026). The employer has to inform them of that duty in writing and keep the notice for the duration of the employment.

During an inspection customs compares the people it finds with the immediate reports on file. A missing report is an administrative offence, and it is also the trigger for looking through the rest of the operation, from working time records to minimum wage calculations. How such an inspection runs, and which documents are demanded, is set out in the customs inspection for undeclared work.

Short term employment carries a wrinkle of its own. It is reported under section 28a SGB IV as well, with its own person group key and a statement of whether further employment exists. The time limits and the test of whether the work is done on a professional basis are set out in seasonal employment and the 70 working day rule.

For an employer the sequence therefore runs the opposite way round to how it feels: the report on day one using the passport details, then registration with the residents office, then the numbers. Employers reviewing their reporting route for a new corridor can find the same detail under employers.