How to Calculate Annualized Working Hours
Annualized working time is a system in which an employee’s total hours are calculated over the whole year, rather than being fixed at a set number of weekly hours such as 35 or 39. To understand how it works, it is important to know how to calculate annualized working hours.
For example, in France, the legal working week is 35 hours, but with annualized hours, employees get greater flexibility in how they spread those hours. This means they can work more during busy periods and take time off when there is less work.
Calcultate annualized worrking hours
Everything you need to know about calculating annualized working hours
Calculating annualized working hours based on the length of the working week:
This table compares the annualized working time calculation for a 35-hour and a 39-hour working week:
| Working week | Annual hours | Days worked (2026 basis: 227 working days) |
|---|---|---|
| 35 hours | 1,607 hours | ≈ 227 days |
| 39 hours | 1,607 hours | ≈ 206 days (≈ 21 RTT days) |
For a 35-hour week, the annual threshold is 1,607 hours (about 227 working days in 2026, after deducting weekends, 25 days of paid leave and the 9 public holidays that fall on weekdays; the 7-hour solidarity day is included). For a 39-hour week, the same 1,607-hour threshold is reached in about 206 days of 7.8 hours: the remaining ≈ 21 days are compensated with RTT days.
Maximum permitted working time
As a general rule, an employee cannot work more than 48 hours in a single week, nor more than 44 hours on average over 12 consecutive weeks (source: Service-Public.gouv.fr). These limits include overtime and are intended to protect employees’ health and well-being. Exceptional derogations may apply, but they are strictly regulated by law.
Do RTT days contradict annualized working time?
From a legal standpoint: Annualizing working time is, in principle, based on a collective agreement (Article L3121-44 of the French Labour Code) that sets the annual working time and, where applicable, the compensatory rest days (“RTT” days) according to the hours worked beyond the legal 35-hour week.
Under this agreement, the employer can adjust the weekly schedule to reach an annual total above the legal working time, while granting rest days known as “RTT”. These days are granted based on the hours worked beyond 35 hours per week.
👉 This arrangement gives both the company and its employees flexibility, using specific reference periods, often the calendar year.
The terms for taking these rest days are also set out in the agreement, which may include rules on notice periods, carrying over unused RTT days, and adjustments for absences, departures or arrivals during the year.
This way, each employee receives RTT days based on their actual working time, which makes it easier to manage fluctuations in activity throughout the year.
What happens if an employee leaves the company before the end of the working year?
If an employee leaves the company before completing a full year under the annualized working time system, the calculation of their hours worked is adjusted to the time actually worked. Here is how it generally works:
Pro rata calculation
The total annual hours are divided by 12 to determine the expected number of hours per month. If the employee leaves before the end of the year, the hours worked up to their departure date are calculated and compared with the total they would have been expected to work over the full year.
Adjusting paid leave and public holidays
All paid leave, such as vacation days or public holidays, must be taken into account. These days are subtracted from the total hours worked to make sure the employee is paid correctly.
Overtime or shortfall in hours
If the employee has worked more hours than planned during this period, they may be entitled to compensation for the extra hours (for example, overtime pay). When the reference period is the year, hours worked beyond 1,607 hours count as overtime (unless the agreement sets a lower threshold). Conversely, if the hours worked are fewer than planned, this could lead to a reduction or adjustment of their final paycheck, depending on the terms of their contract.
Can this system be applied to every company?
You may be wondering whether this system can be set up in your company. First of all, it depends on an agreement between management and employees: in principle, it is based on a company-level or sector-level collective agreement. Without one, the employer can decide alone after consulting the works council (CSE), but only for a limited reference period: at most 9 weeks in companies with fewer than 50 employees and at most 4 weeks above that. Second, it is mainly used in sectors where workload varies over the year, making a fixed schedule less suitable.
How can a working time calculator help you?
To adapt to this system more easily, use our annualized working hours calculator: enter your weekly hours, your paid leave and the public holidays that fall on weekdays, and get your days worked, RTT days and any overtime in seconds.
Annualized working hours calculator (2026)
Enter your weekly hours to calculate your RTT days.
Indicative estimate based on the 1,607-hour legal threshold; your collective agreement may set different rules.
To go further, time tracking software does more than track total time worked: it shows exactly how much time went into each task, which can improve your productivity.
In short, it is important to track these hours so that both employers and employees are clear on expectations and stay within legal limits. For companies, this makes it easier to manage labor costs, while employees gain more control over their schedule, improving their work-life balance. Accurately calculating these hours ensures compliance with labor laws and protects everyone’s rights.
Frequently Asked Questions About Annualized Working Hours
What is annualized working time?
Annualized working time spreads a set number of working hours over the whole year instead of over each week. Weekly hours can go up in busy periods and down in quiet ones, as long as the annual total is respected. In France it is, in principle, set by a collective agreement (Article L3121-44 of the Labour Code).
How many hours a year is a 35-hour week?
In France, a 35-hour week corresponds to an annual threshold of 1,607 hours, which includes the 7-hour solidarity day. In 2026 that is about 227 working days, after deducting weekends, 25 days of paid leave and the 9 public holidays that fall on weekdays.
What is the maximum number of hours an employee can work?
As a general rule, an employee cannot work more than 48 hours in a single week, nor more than 44 hours on average over 12 consecutive weeks. These limits include overtime, and any derogation is strictly regulated by law.
Are RTT days incompatible with annualized working time?
No. RTT days compensate the hours worked beyond 35 hours per week. For example, with a 39-hour week the 1,607-hour threshold is reached in about 206 days of 7.8 hours, so roughly 21 days are compensated with RTT days.
What happens if an employee leaves before the end of the year?
The annual hours are recalculated pro rata to the time actually worked. If the employee worked more hours than planned, they may be entitled to compensation; if they worked fewer, their final pay may be adjusted depending on their contract.
Can any company use annualized working time?
It mainly depends on a collective agreement at company or sector level. Without one, the employer can decide alone after consulting the works council (CSE), but only for a limited reference period: at most 9 weeks in companies with fewer than 50 employees and at most 4 weeks above that.
