Payroll in Thailand: Employer Costs, SSO and Withholding Tax Explained

Hiring employees in Thailand involves more than agreeing on a monthly salary. Employers also need to calculate personal income tax, deduct Social Security contributions, file monthly payroll tax returns and keep clear payroll records.

For companies entering Thailand, understanding these costs early makes budgeting much easier. It also reduces the risk of missed filings and incorrect deductions.

This guide explains Thailand withholding tax on salaries, PND.1 filing, Social Security contributions and what a THB 100,000 monthly salary can actually cost an employer.

Key Takeaways

Employers must calculate and deduct personal income tax from employee salaries.

Salary withholding tax is reported through PND.1.

Thailand uses progressive personal income tax rates from 0% to 35%.

From January 1, 2026, the maximum salary base for Section 33 Social Security increased to THB 17,500. The maximum contribution is therefore THB 875 from the employee and THB 875 from the employer each month.

Employers should budget for salary plus employer Social Security and any additional benefits or employment costs.

Businesses that do not want to manage calculations and monthly filings internally can consider payroll outsourcing.

Thailand Personal Income Tax Brackets

Thailand salary withholding tax is based on the employee's estimated annual taxable income. The employer generally annualizes the monthly salary, applies eligible deductions and allowances, calculates annual tax and then determines the amount to withhold during the year. The Revenue Department provides this annualization method for employment income.

The progressive personal income tax brackets are:

Annual taxable income

Tax rate

THB 0–150,000

Exempt

THB 150,001–300,000

5%

THB 300,001–500,000

10%

THB 500,001–750,000

15%

THB 750,001–1,000,000

20%

THB 1,000,001–2,000,000

25%

THB 2,000,001–4,000,000

30%

Over THB 4,000,000

35%

These rates apply to taxable income rather than simply the employee's gross salary.

For salary income, tax calculations can include the standard employment expense deduction and personal allowances. Employees may also have deductions for items such as Social Security, children, insurance, retirement investments, or other qualifying expenses.

PND.1 Filing in Thailand

PND.1 filing in Thailand is one of the main monthly payroll obligations for employers.

PND.1 reports personal income tax withheld from salaries, wages, bonuses and other employment-related payments. The Revenue Department requires employers to withhold tax when paying employment income and report it through the relevant withholding return.

The normal withholding-tax deadline is within seven days after the end of the month in which the income was paid. Electronic filing receives an additional eight-day filing period, making the practical e-filing deadline generally the 15th of the following month.

The Revenue Department has also required employers to submit PND.1 electronically since 2024.

Payroll teams therefore need a reliable monthly process covering salary calculations, tax deductions, submission and payment.

Social Security: The 5% + 5% Split and 2026 Cap

For employees insured under Section 33, Social Security in Thailand for employers works through matching contributions.

The employee contributes 5% of the applicable salary base and the employer contributes another 5%.

A major change took effect on January 1, 2026. The maximum salary used to calculate contributions increased from THB 15,000 to THB 17,500 for 2026–2028. This raises the maximum monthly contribution from THB 750 to THB 875 for each side.

For example:

Employee contribution: maximum THB 875

Employer contribution: maximum THB 875

Total paid into Social Security: maximum THB 1,750 per month

The Social Security Office indicates contributions are normally due by the 15th of the following month. If the 15th falls on an official holiday, payment can be made on the next working day.

Worked Example: THB 100,000 Monthly Salary

Consider an employee receiving a fixed salary of THB 100,000 per month, or THB 1.2 million annually.

For a simple illustration, assume the employee is single and has no additional deductions beyond the standard employment deductions, personal allowance and statutory Social Security.

After deductions and allowances, part of the employee's taxable income falls into the 25% PIT bracket. Using the Revenue Department's progressive system, monthly salary withholding would be approximately THB 10,200, although the exact figure depends on the employee's declared allowances and payroll circumstances.

Social Security would be capped at THB 875.

A simplified monthly picture would therefore look like this:

Item

Approximate amount

Gross salary

THB 100,000

Employee SSO

THB 875

Estimated PIT withholding

THB 10,200

Approximate net pay

THB 88,925

Employer SSO

THB 875

Basic employer payroll cost

THB 100,875

The employer's actual employment cost may be higher once bonuses, insurance, allowances, provident funds or other benefits are included.

You can estimate your costs before making a new hire.

Payslip and Payroll Record Requirements

Good payroll records are essential in Thailand.

Department of Labour Protection and Welfare payroll templates show records covering salary, overtime, holiday pay, Social Security deductions, tax deductions, total payments and net amounts.

In practice, a clear payslip should show gross salary, additional earnings, deductions, withholding tax, Social Security and net pay.

Employers should also keep payroll information consistent across employment contracts, bank payments, PND.1 filings and Social Security submissions. Differences between these records can create problems during an audit or employee dispute.

Common Payroll Mistakes

One common mistake in 2026 is continuing to use the old THB 750 Social Security maximum instead of the new THB 875 cap.

Other problems include calculating tax as a flat percentage instead of using progressive PIT rates, forgetting to recalculate withholding after bonuses or salary increases, missing monthly PND.1 deadlines and failing to update employee deductions when their circumstances change.

Payroll can quickly become difficult as headcount grows, especially when a company employs both Thai and foreign staff.

FAQs

Is Thailand withholding tax on salary a flat rate?

No. Employment income is generally taxed using progressive personal income tax rates ranging from 0% to 35%.

What is the maximum employer Social Security contribution in 2026?

For a Section 33 employee earning at least THB 17,500 per month, the maximum employer contribution is THB 875 per month. The employee contributes another THB 875.

When is PND.1 due?

PND.1 is a monthly withholding-tax filing. Employers filing electronically generally have until the 15th of the following month under the electronic filing extension.

Make Payroll Costs Easier to Plan

Payroll is a recurring compliance responsibility, so small calculation errors can become expensive when repeated across several employees and months.

Before hiring, understand the complete cost of salary, withholding tax and employer Social Security.

Try the payroll calculator to estimate your Thailand payroll costs.