This rule is regulated under French law. If you don't depend on the French law, we advise you to dismiss this column.
In France, how does it work ?
The employees are paid on a monthly basis, i.e. they always receive the same salary, whether the month lasts 29 or 31 days.
In a year, there are 52 weeks for 12 months. So on average, we have 4.3333 weeks per month. This is the magic number for any payroll accountant !
The monthly salary or theoretical contract is an average obtained by multiplying the employee's weekly contract time by 4.3333.
That is, for a 35h employee: 35 x 4.3333 = 151.67 or 151h40
In reality, there are rarely 4.3333 weeks in a month. Your employee will rarely, if ever, work 151.40 hours per month. Yet he will receive the same pay.
This figure is therefore the theoretical monthly contract time. It is indicative, it should never be used to calculate an employee's overtime, additional or missing hours and it should never be compared to the hours actually worked.