What Is an Automatic Overtime Calculation System and How Does It Help HR Calculate OT?

An automatic overtime calculation system helps HR calculate overtime pay accurately in line with labour law, without calculating each employee’s OT manually in Excel. The system automatically uses clock-in and clock-out records, day types, and employee conditions to calculate OT. It supports 1.5x, 2x, and 3x overtime rates, reducing errors and saving HR many hours each month.

 

When Should an Organisation Use an Automatic OT Calculation System?

Overtime work, commonly known as OT (overtime), is now common in organisations of all sizes. However, without payroll software, the person responsible for calculating wages or compensation must handle many complex details, such as:

 

• The organisation has multiple departments
• Employees have different clock-in and clock-out times
• Employees work different shifts
• Employees switch shifts
• Monthly and daily employees require different OT calculations

 

Consider the Following Overtime Example

Mr. A is a monthly employee earning THB 15,000. He works on Saturday, a normal working day, from 9:00 a.m. to 6:00 p.m. and continues working overtime from 6:39 p.m. until 5:00 a.m. on Sunday, which is a company holiday.

 

Mr. A’s OT Calculation

OT on a normal working day: (15,000/30/8) × 1.5 × 5 = THB 468.75

 

*Note: OT is calculated as 5 hours because any period of less than 30 minutes is rounded down.

Holiday OT: (15,000/30/8) × 3 × 5 = THB 937.50

 

Summary: Mr. A receives total OT pay of THB 1,406.25.

The example above covers only one employee, yet it already involves many calculation details that can cause delays. Payroll software helps reduce multiple work steps, making OT calculations faster, more convenient, and more efficient. The calculation formulas used by the software also follow the applicable principles of the Ministry of Labour.

 

 

How Many Types of OT Are There, and What Rate Applies to Each Type by Law?

There are three main types of OT. The OT calculation methods used by payroll software in accordance with Ministry of Labour principles can be divided into the following three cases:

 

OT Type	When It Applies	Pay Rate (Minimum)
1.5x OT	Work performed outside normal hours on a regular working day	1.5 x/hour
2x OT	Work performed during normal working hours on a holiday	2 x/hour
3x OT	Work performed outside normal hours on a holiday	3 x/hour

 

1. Overtime Pay on a Normal Working Day

Overtime pay on a normal working day must be at least 1.5 times the employee’s normal hourly wage.

 

Example for a Monthly Employee

Mr. A earns THB 10,000 per month and works three hours of overtime after his normal working hours on a working day.

 

Calculation = (10,000 / 30 / 8)*1.5*3

Summary: Mr. A receives THB 187.50 in overtime pay for work performed after normal hours on a regular working day.

 

2. Pay for Working on a Holiday

Pay for working on a holiday can be divided into two cases:

 

• Monthly employees receive holiday work pay equal to at least their normal hourly wage (1x).
• Daily employees receive holiday work pay equal to at least twice their normal hourly wage (2x).

 

This point often causes confusion. In practice, both cases result in total compensation equal to 2 times the normal hourly wage. Monthly employees are already paid for the holiday through their monthly salary, so an additional payment equal to the normal hourly wage (1x) is added, producing total compensation equal to twice the normal rate (2x).

 

For example: Mr. D, a monthly employee, has an hourly wage of THB 62.50. The additional holiday payment at 1 times the hourly rate is THB 62.50. When added to the THB 62.50 already included in his salary, the total is THB 125.

 

3. Overtime Pay on a Holiday

For overtime performed on a holiday, such as a public holiday, traditional holiday, or the company’s regular weekly holiday, employees must receive at least 3 times their normal hourly wage.

 

How Does Manual OT Calculation Differ from an Automatic OT Calculation System?

 

Comparison Point	Manual / Excel OT Calculation	Automatic OT Calculation System
Working-Time Data	Data must be collected and imported manually	Uses working-time data already stored in the system
Work Shifts	HR must check each shift individually	Calculates according to configured shifts and conditions
OT Rates	HR must create and maintain formulas manually	Rates can be configured according to company policy
Historical Review	HR must search through previous files	Historical data is easier to review in the system

 

Summary:  How an Automatic  OT Calculation System Helps  HR 

Complex OT calculations can cause delays and increase the risk of errors. HumanSoft payroll software automatically calculates OT with functions that cover all calculation cases based on Ministry of Labour principles. It also allows organisations to:

• Add or rename OT types according to company policy, such as public-holiday OT
• Adjust the OT rate for each OT type 
• Configure fixed-amount OT payments, such as THB 800 for three hours
• Set a fixed hourly OT rate, such as THB 90 per hour, with actual OT pay based on the number of hours worked
• Configure separate OT settings for monthly and daily employees
• Add special OT conditions, such as treating employee travel time as OT income instead of using an attendance allowance
  
  

Therefore, payroll software that automatically calculates OT in line with Ministry of Labour principles and provides flexible functions for each company is essential for organisations that need to calculate OT accurately and on time. HumanSoft payroll software  automatically calculates OT in accordance with legal requirements, allows organisations to configure every OT rate, and connects directly with the time-attendance system.

 

FAQ: Frequently Asked Questions About OT Calculation Software

Q: What is OT calculation software?

A: OT calculation software processes working-time records, shifts, day types, and overtime rates to calculate employees’ OT hours and overtime pay according to the conditions configured by the organisation.

 

Q: What is the overtime rate for work performed after normal hours on a holiday?

A: Employees must receive overtime pay of at least 3 times their normal hourly wage.

 

Q: Can OT calculation software support employees working multiple shifts?

A: This depends on the software selected. A system with Time Attendance and Shift Management can use shift data and clock-in and clock-out times to calculate OT. Companies should therefore test the system with their actual shift patterns before purchasing it.

 

Q: How much does HumanSoft’s OT software cost?