Tax filing for 2026 involves summarizing all income earned during the 2025 tax year (1 Jan – 31 Dec 2025) to calculate and report to the Revenue Department. The following is a simplified overview.
Paper filing: from 1 January to 31 March 2026 (submit at local Revenue offices).
Online filing (e-Filing): from 1 January to 8 April 2026 (an 8-day extension compared to paper filing).
By law, individuals whose income reaches the threshold "must file" even if no tax is owed after calculation. Filing categories depend on "status" and "income sources" as follows:
Minimum income thresholds requiring filing (for singles):
For salary income only (Section 40(1)): filing is required if income exceeds 120,000 THB/year.
For other types of income or combined salary and other income: filing is required if total income exceeds 60,000 THB/year.
P.N.D. 91: for individuals with salary income only.
P.N.D. 90: for individuals with other income included (e.g., freelance work, online sales, rental income, dividends).
The thresholds for "filing a tax return" and "owing tax" differ:
Income below 10,000 THB/month (120,000 THB/year): no filing or tax payment required.
Income between 10,001 and 26,583 THB/month: filing required but no tax payment yet, as net income after expenses and personal deductions does not exceed 150,000 THB, which is tax-exempt.
Income above 26,583 THB/month: filing required and tax payment starts, subject to deductions such as life insurance, children, or mortgage interest that may reduce or eliminate tax liability.
You can file yourself via the Revenue Department's website as follows:
Visit the website: go to efiling.rd.go.th
Log in: use your 13-digit ID number and password (first-time users must register).
Verify data: the current system includes a My Tax Account that automatically imports some salary data and deductions (e.g., social security, parental support) for review.
Enter income: input all income as shown on your form 50 ทวิ provided by your employer.
Enter deductions: add any additional eligible deductions you have.
Review tax amount: the system immediately calculates whether you "owe additional tax" or "will receive a refund."
Confirm submission: click agree and print the document to keep as proof.
Withholding tax certificate (form 50 ทวิ): crucial as it shows your income and tax withheld during the year.
Deduction evidence: such as life insurance receipts, mortgage interest documents, and information on children or parents supported.