How to Calculate the Salary of an Employee on a Days-Based Annual Pay System Hired Mid-Year

Why Does Hiring an Employee on a Days-Based Annual Pay System Mid-Year Create Payroll Calculation Challenges?

The days-based annual pay system (forfait annuel en jours), governed by Articles L.3121-58 and following of the French Labour Code, is a working time arrangement designated for autonomous executives and certain employees whose working time cannot be predetermined. When an employee on this system is hired mid-calendar year or during the reference period, two distinct calculations must absolutely be performed by the payroll department:

• Prorating the salary for the first incomplete month of work;
• Prorating the number of days to be worked for the remainder of the reference period.

These two operations follow strict rules, often poorly understood, and failure to comply can expose the employer to salary back-pay and disputes before the labor court (conseil de prud’hommes). This article details the mandatory methodology, supported by formulas, along with a complete numerical example. For a comprehensive overview of payroll mechanisms, see our complete payroll guide.

What Is the Mandatory Method for Prorating the Salary of an Employee on a Days-Based Annual Pay System for Their First Month?

Contrary to what some payroll software may default to, the prorating of the salary for the first month of an employee on a days-based annual pay system is carried out exclusively using calendar days. It is strictly prohibited to prorate based on working days, business days, or the thirtieth (or thirty-first) rule.

The applicable formula is as follows:

Salary for the month = Monthly Salary − (Monthly Salary ÷ Number of Calendar Days in the Month × Number of Non-Worked Calendar Days Before Hiring)

This formula results from the combined application of Articles L.3242-1 (monthly payment of salary) and L.3121-58 and following of the French Labour Code. The use of calendar days is justified because the days-based annual pay system deviates from the hourly accounting of working time: referencing calendar days is the only neutral and compliant option with the essence of the system.

Why Are Other Proration Methods Prohibited?

The thirtieth (or thirty-first) rule is a mechanism derived from jurisprudence applicable to employees whose working time is measured in hours. Applying it to an employee on a days-based annual pay system would create an artificial distortion, sometimes benefiting, sometimes disadvantaging the employee, depending on the actual number of calendar days in the month of hiring. Similarly, prorating via working days or business days is inappropriate for the days-based pay system, which relies on a count of working days and rest days over the year, rather than on a weekly five or six-day logic.

The Court of Cassation has repeatedly emphasized that agreements on days-based systems must be interpreted strictly, and any calculation method not explicitly outlined in the applicable collective agreement or by law is subject to challenge (Cass. soc., June 29, 2011, No. 09-71.107). Therefore, it is imperative to adhere to the method of calendar days, which is the only method compliant with the texts.

How to Calculate the Number of Days to Work for the Remainder of the Reference Period After Mid-Year Hiring?

The second calculation involves determining the number of days the employee must effectively work between their hiring date and the end of the reference period (usually December 31 for a calendar year). This operation follows a mandatory five-step method (a → e) that we detail below.

Step (a): Determine the Remaining Calendar Days in the Reference Period

This involves counting the total number of calendar days between the hiring date (inclusive) and the last day of the reference period (inclusive). For example, for a hiring date of April 15 in a fiscal year aligned with the calendar year, count from April 15 to December 31, totaling 261 calendar days.

Step (b): Subtract Weekly Rest Days

Next, subtract all Saturdays and Sundays (or weekly rest days according to the collective agreement) included in the period. Article L.3132-1 of the French Labour Code guarantees weekly rest of at least 24 consecutive hours, in addition to the 11 hours of daily rest, totaling 35 consecutive hours. For our example from April 15 to December 31, we typically identify 74 weekly rest days (Saturdays and Sundays).

Step (c): Subtract Public Holidays Coinciding with Normally Worked Days

Only subtract public holidays that fall on a normally worked day (generally Monday to Friday). Public holidays that fall on a Saturday or Sunday do not need to be deducted as they are already neutralized in step (b). Articles L.3133-1 and L.3133-7 to L.3133-12 of the French Labour Code specify the list of legal public holidays. For the period from April 15 to December 31, 2026, for example, we identify 6 public holidays that fall on a working day (May 1, May 8, July 14, Ascension Thursday, August 15, November 1, December 25, depending on the year — the exact count would vary with the year’s calendar).

Step (d): Subtract Prorated Paid Leave Entitlements

An employee hired mid-year acquires prorated paid leave entitlements in accordance with Article L.3141-1 of the French Labour Code. These entitlements must be estimated and deducted from the number of days to be worked. For an employee hired on April 15, the acquired rights for the remaining reference period are calculated pro rata temporis. If the employee has not acquired any paid leave entitlements (first year of employment without carryovers), this step may yield zero, but it must still be formalized in the calculation.

Step (e): Subtract Prorated Days Off Related to the Pay System

Days off associated with the pay system (often referred to as “RTT forfait” or “JNT — jours non travaillés”) must also be prorated according to the remaining period in the reference year. The total annual number of days off is derived from the classic formula: 365 days − 104 weekly rest days − X public holidays on working days − 25 vacation days − 218 days worked = Y days off. This number Y is then prorated based on the number of remaining calendar days relative to the total number of calendar days in the fiscal year. The result is rounded up to the nearest half-day in accordance with the most protective practices, unless a collective provision states otherwise.

Final Result and Solidarity Day

The number of days to work is equal to: (a) − (b) − (c) − (d) − (e). If the solidarity day (Article L.3133-7 of the French Labour Code) has not yet been carried out upon the employee’s hiring at a previous employer, it is necessary to add +1 day to the obtained result. It is the employer’s responsibility to verify this point at the time of hiring, by requesting a certification from the previous employer.

What is the Complete Numerical Example for Hiring on April 15 with a Salary of 4,000 Euros and a Quota of 218 Days?

Let’s consider the following assumption: an autonomous executive is hired on April 15, 2026, with a gross monthly salary of €4,000 and an annual quotas of 218 days based on a fiscal year aligned with the calendar year (January 1 – December 31).

Calculation of April Salary

April has 30 calendar days. The employee did not work from April 1 to April 14, which totals 14 calendar days not worked.

Salary for April = 4,000 − (4,000 ÷ 30 × 14) = 4,000 − 1,866.67 = €2,133.33

Calculation of the Number of Days to Work from April 15 to December 31

(a) Calendar days from April 15 to December 31: 261 days

(b) Weekly rest days (Saturdays and Sundays): 74 days

(c) Public holidays on working days (May 1, May 8, Ascension, July 14, August 15, November 1, December 25): 7 days (the exact count will vary depending on the 2026 calendar)

(d) Prorated vacation entitlements: the employee hired on April 15 has not yet acquired any usable vacation days for the current fiscal year, so we retain 0 days (or the number of days carried over if appropriate).

(e) Prorated days off associated with the pay system: For a full year, the number of days off is, for instance, 10 days. Proration: 10 × (261 ÷ 365) = 7.15 days, rounded to 7.5 days.

Final Result: 261 − 74 − 7 − 0 − 7.5 = 172.5 days to work.

If the solidarity day has not yet been carried out: 172.5 + 1 = 173.5 days.

This calculation should be formalized in a document annexed to the employment contract or in an amendment to ensure secure contractual relations and facilitate rigorous tracking of days worked. Use our days-based salary simulator to automate this calculation.

What Are the Most Common Errors Committed by Employers During This Proration?

Disputes arising from the days-based annual pay system during mid-year hiring reveal recurring errors which we list below, along with the associated legal risks:

1. Use of the thirtieth rule for the first month’s pay. This is the most common error. It leads to a salary amount differing from the correct amount, whether favorably or unfavorably to the employee. In both cases, the employee may claim back-pay based on Article L.3242-1 of the French Labour Code, with a three-year statute of limitations (Article L.3245-1).

2. Omission of the prorating of rest days. Some employers assign the full annual rest days to an employee hired mid-year, which artificially decreases the number of working days and may pose difficulties in the case of subsequent departures (settlement discrepancies).

3. Prorating the days to work based on working days instead of calendar days. The method (a) → (e) requires starting with calendar days. Starting with working days skews the entire calculation downstream.

4. Failure to account for the solidarity day. Forgetting the solidarity day is common in mid-year hires, even though the employee may not have always performed this day with the previous employer. Article L.3133-7 of the French Labour Code requires its annual performance.

5. Lack of written formalization of the calculation. Since the days-based agreement constitutes a solemn act requiring the employee’s express consent (Cass. soc., January 31, 2012, No. 10-17.593), the proration of the pay system in the case of mid-year hiring must be formalized in writing, ideally in the employment contract or in an amendment.

How to Integrate the Proration of the Days-Based Pay System with Declaration Obligations in the DSN?

The déclaration sociale nominative (DSN) requires employers to declare monthly the number of days worked by the employee under the days-based annual pay system. In the case of hiring in the middle of the month, the first DSN must reflect:

• The prorated salary in accordance with the formula described above;
• The actual number of days worked in the incomplete month;
• The prorated annual quota applicable to the employee.

It is essential to verify your payroll software configuration on these three points, as DSN anomalies can trigger requests for clarification from the URSSAF or the supplementary pension fund. For further information on payroll mechanisms linked to the days-based annual pay system, see our payroll guide.

What are the Applicable Reference Texts?

The legal framework for the days-based annual pay system in the case of mid-year hiring is based on the following texts:

• Articles L.3121-58 and following of the French Labour Code: general regime of the days-based annual pay system;
• Article L.3242-1 of the French Labour Code: monthly salary payment;
• Article L.3132-1 of the French Labour Code: weekly rest;
• Article L.3133-1 of the French Labour Code: list of legal public holidays;
• Articles L.3133-7 to L.3133-12 of the French Labour Code: solidarity day;
• Article L.3141-1 of the French Labour Code: paid leave.

The employer must also refer to the collective agreement applicable to the branch or company that establishes the days-based pay system, which may provide specific prorating modalities, provided that they are at least as favorable as the legal provisions.

FAQ — Frequently Asked Questions on the Payroll of an Employee on a Days-Based Annual Pay System Hired Mid-Year

Does the calendar days prorating also apply in the case of departure mid-month?

Yes. The calendar days prorating method is symmetrical: it applies both to arrival and departure mid-month. The termination settlement must be calculated according to the same formula, taking into account the number of calendar days actually worked in the last month.

What happens if the employee exceeds the prorated number of days?

If the employee works more days than the prorated quota, the excess days must be handled in accordance with the provisions of Article L.3121-59 of the French Labour Code: the employee can, with the employer’s consent, forgo part of their rest days in exchange for a salary increase of at least 10%, formalized in an amendment to the employment contract.

Can the employer apply a different proration method specified in a collective agreement?

A collective agreement may provide for specific prorating modalities, provided that they are at least as favorable as the legal method. However, the prorating of the salary for the first month using calendar days remains the only method compliant with the provisions of Article L.3242-1 of the French Labour Code. The collective agreement cannot derogate from this in favor of the employee.

How should absences of an employee on a days-based annual pay system hired mid-year be handled?

Absences occurring after hiring are deducted from the prorated quota according to the same rules that apply to an employee present for the full year. Each day of absence (sick leave, unpaid leave, etc.) reduces the number of workdays by one unit and results in a pay deduction calculated based on the daily wage (monthly salary ÷ 21.67 working days on average, or according to the applicable collective method).

Is it necessary to provide a summary document to the employee?

Article L.3121-65 of the French Labour Code requires the employer to establish a control document showing the number and date of the days or half-days worked. In the case of mid-year hiring, this document must state the applicable prorated quota and track the days worked from the hiring date.

For any questions regarding the management of payroll for an employee on a days-based annual pay system, do not hesitate to contact our firm. You can also use our online days-based salary simulator for instant calculations.