Work on demand
Work on demand means the work is performed according to the volume of work arising. The employer determines the timing at short notice, and in return section 12 TzBfG protects employees with four firm rules.
As of:September 2026
The four protective rules
First: the agreement has to fix a specific duration of weekly and daily working time. Where the weekly figure is missing, 20 hours are deemed agreed. Where the daily figure is missing, the work has to be called on for at least three consecutive hours.
Second: the call has to come at least four days in advance, otherwise the person is not obliged to work.
Third: where a minimum working time is agreed, the employer may call on at most 25 percent above it. Where a maximum working time is agreed, it may call on at most 20 percent below it.
Fourth: for calculating continued pay in case of illness and on public holidays, the average working time of the last three months is decisive.
MetronHR works these figures out itself: time accounts, premiums, overtime and the limits of the German Working Hours Act, with every booking.
Why the 20-hour rule gets expensive
It applies automatically where the contract states no number of weekly hours. Anyone actually deploying someone for eight hours a week still owes pay for 20 as soon as somebody relies on it.
For a mini-job that blows the earnings limit: 20 hours a week is around 87 hours a month, so at the minimum wage of 13.90 euros a good 1,200 euros. The mini-job retroactively becomes employment subject to social security contributions.
Example: a temporary worker with no hours stated in the contract
- Contract with no number of weekly hours, in fact about 8 hours a week.
- Statutory consequence: 20 hours are deemed agreed (section 12(1) TzBfG).
- Per month: 20 × 4.348 = 86.96 hours.
- At 13.90 euros: 1,208.74 euros owed, far above the mini-job limit of 603 euros.
Common mistake
The contract says "as required" instead of a number of hours. That is not flexibility but the statutory fiction of 20 weekly hours, and it takes effect retroactively.
Further reading
- Section 12(1) TzBfG
- „Employer and employee can agree that the employee is to perform their work according to the volume of work arising (work on demand). The agreement has to fix a specific duration of weekly and daily working time. Where the duration of weekly working time is not fixed, a working time of 20 hours is deemed agreed.“
- Section 12(2) to (4) TzBfG
This is not legal advice; for a specific case at your workplace you are better off asking someone qualified to give it.
Published by: AMNAU GmbH
Editorial responsibility: Ugur Aydogan, Product development.
Last reviewed: September 2026
Knowing the terms is one thing. Settling them cleanly is another.
MetronHR keeps time accounts, calculates premiums and checks the limits of the German Working Hours Act automatically. Try it free for 14 days.
No credit card, cancel any time
Related terms
Mini-job
A mini-job is marginal paid employment: the regular monthly pay does not exceed the marginal earnings threshold. In 2026 it is 603 euros a month.
Target hours
Target hours are the hours a person has to work contractually in a period. They are the comparison figure for the hours actually worked and therefore the basis of every time account.
Notice period for rosters
The notice period is the lead time with which the timing of working time has to be communicated before it becomes binding.
Midi-job
A midi-job is employment in the transitional band: the regular pay is above the marginal earnings threshold but not above 2,000 euros a month.