Incomplete Month Salary Calculator
Calculate prorated salary for employees who joined or resigned mid-month — MOM formula
Excludes rest days and public holidays
PeopleCentral automatically calculates prorated salaries for mid-month joiners and leavers. No manual calculations. No errors.
See how payroll worksFor reference only. Verify with MOM and IRAS for official figures.
When does the incomplete month salary rule apply?
Any time an employee does not work a complete calendar month, their salary needs to be prorated. This happens when a new employee joins mid-month, when an employee resigns and their last day is not the end of the month, or when an employee takes unpaid leave for part of the month. Getting this calculation wrong is a common cause of payroll disputes in Singapore.
The MOM formula for incomplete month salary
The Ministry of Manpower sets out a specific formula for calculating prorated salary:
What counts as a working day for proration?
This is where most employers make errors. Working days for salary proration include days when the employee was on paid leave (annual leave, sick leave, etc.). A day on approved paid leave still counts as a working day in both the denominator and numerator of the proration formula.
Days that do not count: Sundays (if your company does not operate on Sundays), gazetted public holidays, and agreed rest days. The exact number of working days will vary by month and by your company's work week structure.
When must prorated salary be paid?
Under the Employment Act, salary must be paid within 7 days of the end of the salary period for employees covered under the Act. For employees on their last month (resignation or termination), the final salary — including any outstanding leave encashment — must be paid within 3 working days of the last day of employment.
Frequently asked questions
How do I calculate salary for an employee who joins on 15 March?
Using the MOM formula: if March has 21 working days and the employee works from 15 March to 31 March (13 working days), their prorated salary is (monthly salary ÷ 21) × 13. A S$4,000/month employee would receive S$4,000 ÷ 21 × 13 = S$2,476.19.
Does annual leave count as a worked day for proration?
Yes. Paid leave days (annual leave, sick leave, hospitalisation leave) count as both working days in the denominator and days worked in the numerator. They do not reduce the prorated salary calculation. Only unpaid leave days are excluded from days worked while still remaining in the denominator.
What happens if a public holiday falls during an employee's notice period?
Public holidays during the notice period are treated as normal public holidays — the employee is entitled to the day off and the public holiday day is not included in the working day count for salary proration purposes.
How soon must I pay an employee's final salary?
Within 3 working days of the last day of employment for employees leaving (resignation or termination). This includes any outstanding salary, unused annual leave encashment, and any other payments owed. Late payment is an offence under the Employment Act.