On-Call Duty – Definition, Legal Framework & HR Best Practices

On-call duty (Bereitschaftsdienst) is a special form of working time in which employees are required to remain at a location designated by the employer so that they can start work immediately if needed — even when they are not actively working during that time. According to the case law of the European Court of Justice (ECJ), on-call duty counts in full as working time and must be remunerated accordingly and taken into account when calculating statutory maximum working hours. HR professionals must clearly distinguish on-call duty from standby duty (Rufbereitschaft), as different rules apply to each.

What Is On-Call Duty?

On-call duty (Bereitschaftsdienst) applies when employees are required by their employer to remain at a specific location — typically the workplace or nearby accommodation — ready to begin work at any moment, even if no active work takes place during that period.

The decisive distinguishing factor is spatial restriction: employees cannot freely choose where they stay. This is precisely what sets on-call duty apart from standby duty, where employees are generally free to be wherever they choose.

Industries where on-call duty is particularly common include healthcare (physicians, nursing staff), fire and rescue services, IT operations and technical support, and the energy and water supply sector.

On-Call Duty, Standby Duty, Work Readiness – What Is the Difference?

These three special forms of working time are frequently confused. The following overview clarifies the distinctions:

*Exception: If standby duty is subject to such strict restrictions (e.g., very short response times, severely limited radius of movement) that it is effectively equivalent to on-call duty, it may also count as working time. The ECJ clarified this in the Matzak ruling (C-518/15, 2018).

On-Call Duty

During on-call duty, employees are physically present and must be immediately ready for deployment. The entire period — including phases of inactivity — counts as working time under § 2 of the German Working Hours Act (ArbZG) and ECJ case law.

Standby Duty

During standby duty (Rufbereitschaft), employees are free to be wherever they choose. However, they must remain reachable at all times and be able to start work within a reasonable period. Only the time actually worked (e.g., responding to a call-out) counts as working time — not the standby period itself.

Work Readiness

Work readiness (Arbeitsbereitschaft) applies when employees are present at the workplace and alert but not actively working — for example, a bus driver waiting between trips or a firefighter on duty in the station. This also counts in full as working time.

Legal Framework

The German Working Hours Act and EU Working Time Directive

The German Working Hours Act (Arbeitszeitgesetz, ArbZG) provides the national legal basis for regulating on-call duty. Under § 2 ArbZG, working time is defined as the period from the start to the end of work, excluding rest breaks. Since on-call duty meets this definition, it counts in full as working time.

The EU Working Time Directive 2003/88/EC establishes as a binding EU standard that average weekly working time, including overtime, must not exceed 48 hours. Since on-call duty is working time, it is included in this calculation.

On-Call Duty as Working Time – ECJ Case Law

ECJ case law provides the decisive legal anchor for classifying on-call duty:

• ECJ C-303/98 (SIMAP, 2000): On-call duty performed by physicians at health centres counts in full as working time — even when periods of inactivity predominate.
• ECJ C-151/02 (Jaeger, 2003): Medical on-call duty in a hospital requiring physical presence is fully working time, even when the physician is sleeping.
• ECJ C-518/15 (Matzak, 2018): Standby duty with a severely restricted radius of movement and very short response times can be equivalent to on-call duty and therefore count as working time.

These rulings are binding on all EU member states and have a direct impact on practice in German companies.

Maximum Working Hours and Collective Agreement Exemptions

The statutory baseline (§ 3 ArbZG): a maximum of 8 hours per working day, and a maximum of 48 hours per week — including on-call duty.

An extension to 10 hours per day is permissible if the average of 8 hours per day is maintained within a reference period of 6 months.

Through collective agreements (Tarifvertrag), further exemptions may be agreed in certain industries under § 7 ArbZG. In the healthcare sector, for example, the weekly working time may be extended to up to 60 hours where a significant proportion of working time consists of on-call duty. Importantly, such deviations always require a valid collective agreement.

Also worth noting: on-call duty interrupts the statutory minimum rest period of 11 hours (§ 5 ArbZG). After on-call duty ends, the rest period starts afresh.

Remuneration During On-Call Duty

Minimum Wage and Flat-Rate Pay

On-call duty must be remunerated at least at the statutory minimum wage under the Minimum Wage Act (Mindestlohngesetz, MiLoG). This applies to every hour — including inactive periods.

Flat-rate remuneration arrangements are permissible, as long as the effective hourly rate does not fall below the minimum wage. The basis for calculation is always the total number of hours spent on on-call duty.

Collective agreements may provide for lower hourly rates during inactive phases of on-call duty — but never below the minimum wage threshold.

Supplements for Night, Sunday and Public Holiday Duties

Where on-call duty falls during night-time, Sundays or public holidays, supplementary pay may be due. This typically follows from the applicable collective agreement or individual employment contract. A statutory entitlement to night-work supplements arises indirectly from § 6 ArbZG: employers are obliged to provide night workers with appropriate compensation — either through paid days off or through pay supplements.

Practical Implementation – Checklist for Employers

Introducing and managing on-call duty in a legally compliant manner requires clear rules in several areas:

Employment contract and collective agreement:

• The obligation to perform on-call duty must be expressly agreed in the employment contract or collective agreement
• Clearly define the remuneration model (hourly rate, flat-rate, supplements)
• Include a reference to any applicable collective agreement

Working time recording:

• Document the start and end of every on-call duty period
• Record active deployment time within on-call duty separately
• Monitor total weekly and monthly hours (maximum working time limits)

Rest periods:

• Ensure that the 11-hour rest period is observed after each on-call duty period
• Record any exemptions (if agreed by collective agreement) in writing

Compliance review:

• Regularly review existing remuneration models for minimum wage compliance
• Monitor ECJ and Federal Labour Court (BAG) case law — this is an active area of law
• Seek advice from a specialist employment lawyer where there is any uncertainty

Frequently Asked Questions About On-Call Duty

What is the difference between on-call duty and standby duty?

The decisive criterion is spatial freedom. During on-call duty, employees must remain at a location designated by the employer — this makes the entire period working time. During standby duty, employees can freely choose their location; only the time actually worked (e.g., a specific call-out) counts as working time. Exception: where the effective freedom of movement is so restricted that standby duty is equivalent to on-call duty, it also counts as working time (ECJ, Matzak 2018).

Does on-call duty count as working time?

Yes — in full. This applies even to periods of inactivity within on-call duty. This classification is based on § 2 ArbZG and the binding rulings of the ECJ (SIMAP 2000, Jaeger 2003). Employers must therefore take on-call duty into account when ensuring compliance with daily and weekly maximum working hours.

How must on-call duty be remunerated?

At minimum at the statutory minimum wage under MiLoG — for every hour of on-call duty. Flat-rate arrangements are permissible as long as the effective hourly rate does not fall below the minimum wage. Collective agreements may provide for different (including lower) rates for inactive phases, but not below the minimum wage threshold. Supplements for night, Sunday and public holiday duties are governed by the relevant collective agreement or employment contract.

How many hours of on-call duty per week are permitted?

The statutory baseline: a maximum of 8 hours per working day and 48 hours per week (§ 3 ArbZG) — including on-call duty. An extension to 10 hours per day is possible if the average of 8 hours is maintained within a 6-month reference period. Collective agreements may permit further exemptions in certain industries such as healthcare (§ 7 ArbZG).

What must be covered in the employment contract regarding on-call duty?

The obligation to perform on-call duty must be expressly agreed in the employment contract or collective agreement — a unilateral instruction by the employer without a contractual basis is not permissible. In addition, the remuneration model, any supplements, and references to applicable collective agreements should all be clearly defined.

Does on-call duty count as a rest period?

No. On-call duty interrupts the statutory minimum rest period of 11 hours (§ 5 ArbZG). After on-call duty ends, the 11-hour rest period starts again from scratch. Exceptions are only possible through collective agreement (§ 7 ArbZG).

In which industries is on-call duty particularly common?

On-call duty is most prevalent in essential services: healthcare (physicians and nursing staff in hospitals), fire and rescue services, energy and water supply, IT operations (e.g., system administration), and security services. These industries often have sector-specific collective agreements that regulate deviations from the statutory baseline.

Conclusion

On-call duty is working time — in full and without exception. This ECJ classification has direct consequences for remuneration, working time recording, and compliance with maximum hours limits. HR professionals must clearly distinguish on-call duty from standby duty and work readiness, as the legal implications differ significantly.

Key takeaways: the contractual basis must be solid, time recording must be complete, and remuneration must not fall below the statutory minimum wage. In industries governed by collective agreements, it is worth regularly reviewing whether existing arrangements still reflect the current state of ECJ and Federal Labour Court case law.

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Sources

• German Working Hours Act (ArbZG). Federal Ministry of Labour and Social Affairs, 2023. https://www.gesetze-im-internet.de/arbzg/
• EU Working Time Directive 2003/88/EC. European Parliament / Council of the EU, 2003. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32003L0088
• ECJ, Judgment C-303/98 (SIMAP). European Court of Justice, 2000. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:61998CJ0303
• ECJ, Judgment C-151/02 (Jaeger). European Court of Justice, 2003. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:62002CJ0151
• ECJ, Judgment C-518/15 (Matzak). European Court of Justice, 2018. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:62015CJ0518
• Minimum Wage Act (MiLoG). Federal Ministry of Labour and Social Affairs, 2023. https://www.gesetze-im-internet.de/milog/
• Guide to Working Time Management. Federal Ministry of Labour and Social Affairs (BMAS), 2023. https://www.bmas.de/SharedDocs/Downloads/DE/Publikationen/a120-leitfaden-arbeitszeitgestaltung.pdf
• Dütz, W. / Thüsing, G.: Arbeitsrecht [Labour Law]. C.H. Beck, 2023.