In this FAQ, we explain the calculation logic of the 13th salary when the payment is made in November, and how the settings with extrapolation or without extrapolation affect the result in Atlanto.
Basic principle
When the 13th salary is paid in November, two options are available.
With extrapolation
It is assumed that the average salary from January to November will also be paid in December.
The 13th salary paid in November usually already corresponds to the effective annual amount.
In December, no adjustment or only a small adjustment is required.
Without extrapolation
The December salary is not taken into account in the November calculation.
In December, an adjustment is made so that the 13th salary corresponds to the effective annual salary.
Example 1 Constant salary throughout the year
Parameters
Employment start: 1 January
Salary January–December: CHF 6,000
No salary increase
Employee 1 With extrapolation
November
Total salary January–November: CHF 66,000
Calculation months: 11
Monthly salary: 66,000 / 11 = CHF 6,000
December
Effective 13th salary: 72,000 / 12 = CHF 6,000
Adjustment: CHF 0
The 13th salary is already correct in November.
Employee 2 Without extrapolation
November
Total salary January–November: CHF 66,000
Calculation months: 12
Monthly salary: 66,000 / 12 = CHF 5,500
December
Effective 13th salary: 72,000 / 12 = CHF 6,000
Adjustment: CHF 500
Part of the 13th salary is paid retrospectively in December.
Example 2 Salary increase during the year
Parameters
Employment start: 1 January
Salary January–August: CHF 6,000
Salary September–December: CHF 8,000
Employee 1 With extrapolation
November
Total salary January–November: CHF 72,000
Calculation months: 11
Monthly salary: CHF 6,545.45
December
Effective 13th salary: 80,000 / 12 = CHF 6,666.67
Adjustment: CHF 121.21
Employee 2 Without extrapolation
November
Total salary January–November: CHF 72,000
Calculation months: 12
Monthly salary: CHF 6,000
December
Effective 13th salary: CHF 6,666.67
Adjustment: CHF 666.67
Example 3 Employment start during the year and salary increase
Parameters
Employment start: 1 April
Salary April–August: CHF 6,000
Salary September–December: CHF 8,000
Entitlement: 9/12 of the 13th salary
Employee 1 With extrapolation
November
Total salary April–November: CHF 54,000
Calculation months: 8 of 9 eligible months
Monthly salary: CHF 5,062.50 (CHF 54,000 / 8 x 9/12)
December
Effective 13th salary: CHF 5,166.67
Adjustment: CHF 104.17
Employee 2 Without extrapolation
November
Total salary April–November: CHF 54,000
Calculation months: 9
Monthly salary: CHF 4,500 (CHF 54,000 / 9 x 9/12)
December
Effective 13th salary: CHF 5,166.67
Adjustment: CHF 666.67
Summary
With extrapolation
Realistic payment already in November
No or minimal adjustment in December
Without extrapolation
Lower payment in November
Compensation or adjustment in December
Recommendation
When paying the 13th salary in November, extrapolation is in most cases more transparent and closer to the effective annual salary.