ยื่นภาษี 2568: 2025 Deadlines, Forms & Online Guide

Tax season in Thailand brings a familiar mix of deadlines and paperwork, but with a few twists that can trip up even seasoned filers. The key dates for filing your 2025 income tax return (year 2568) are now set, with online filing from March 1 to April 8, 2026.

Thai personal income tax filing period 2025: March 1 – April 8, 2026 (online) ·
Mid-year tax form (PND 94) deadline: September 1 – October 8, 2025 ·
Official online filing platform: D-MyTax by Revenue Department ·
Annual paper filing deadline: March 31, 2026

Six key facts, one pattern: the Revenue Department has fixed the deadlines with a clear separation between online and paper filing, and the mid-year return adds an extra obligation for certain taxpayers.

Online Tax Filing 2025: When is the Deadline?

Online filing period: March 1 – April 8, 2026

• The Revenue Department’s e-Filing system (D-MyTax) opens for annual personal income tax returns on March 1, 2026, and closes at midnight on April 8, 2026 (PwC Tax Summaries (global tax advisory)).
• This eight-day extension beyond the traditional March 31 deadline has been a standing policy, confirmed through January 2027 (Nishimura & Asahi (legal) policy note).

Paper filing deadline: March 31, 2026

• If you choose to submit a physical return, the deadline is strictly March 31, 2026 — no extension for paper forms (Pattaya Mail (local news)).
• Filing late by paper means you lose the extra eight days that online filers get.

The implication: if you can file online, you should. The Revenue Department clearly incentivizes digital submission.

PND 94 Mid-Year Tax: Filing Deadline 2025

Filing period for PND 94: September 1 – October 8, 2025

• Individuals engaged in business, freelancing, or other income streams outside salaried employment must file a mid-year return (PND 94) for income earned January through June 2025 (PwC Tax Summaries (global tax advisory)).
• The online filing window runs from September 1 to October 8, 2025 (Siam Legal (legal guide)).
• Failure to file PND 94 on time may trigger a surcharge of 0.5% per month on the tax due (Thailand Revenue Department e-Filing (official portal)).

What this means: check your income sources now. If you earned anything outside your salary in the first half of 2025, mark your calendar for September 1.

What Tax Forms Do I Need for 2025 Individual Filing?

PND 90: For income from employment and other sources

• Use PND 90 if you have both salary income and income from business, rent, freelancing, or investments (Revenue Department English e-Service (official portal)).
• This is the most comprehensive form and covers all assessable income categories under the Thai Revenue Code.

PND 91: For income only from employment

• If your sole income is from salaried employment (with or without a single employer), PND 91 is the simpler option (AustCham Thailand / HLB guide).
• It does not require you to itemize business expenses or other income types.

PND 94: Mid-year return for certain income types

• As noted, this is filed mid-year (September-October 2025) for income earned January-June, and covers the same income categories as PND 90 but only for the first half (PwC Tax Summaries (global tax advisory)).
• You still need to file the annual return (PND 90 or 91) by April 2026 to reconcile the full year.

The trade-off: PND 91 is simpler but only works for pure salary earners. If you have any other income, you must use PND 90 and also file PND 94 mid-year.

How to File Tax Online in 2025: Easy Step-by-Step

1. Register on D-MyTax website

   • Go to efiling.rd.go.th (the official D-MyTax portal) and click “Register” (Revenue Department English e-Service (official portal)).
   • You will need your Thai citizen ID number and a valid email address.

2. Log in with citizen ID and password

   • After registration, use your citizen ID and the password you set to log in.
   • If you forget your password, the system offers a recovery option via email.

3. Select personal income tax form

   • Choose the appropriate form: PND 90, PND 91, or PND 94 (if mid-year) (Revenue Department English e-Service (official portal)).
   • The system will pre-fill some basic data from your previous filings if you are a returning user.

4. Auto-fill deductions and allowances

   • Click “Auto-fill” to import deduction data from the Revenue Department’s records — this includes withholding tax (50 Tavi), social security contributions, and provident fund contributions (AustCham Thailand / HLB guide).
   • You can also manually add allowances for life insurance, mortgage interest, charitable donations, etc.

5. Review and submit

   • Double-check all figures, especially income and deductions, before hitting “Submit.”
   • Once submitted, you will receive a confirmation reference number. Save it for your records.

6. Pay tax online or via bank

   • If tax is due, you can pay immediately via credit card, mobile banking (PromptPay QR), or internet banking through the portal (RD Smart Tax app (Google Play, official)).
   • Payment can also be made at any bank counter using the barcode generated by the system.

For first-time filers, the key is preparation: gather your 50 Tavi certificate, bank interest statements, and deduction receipts before you start.

Can I Check My Tax Filing Status Online?

Log in to D-MyTax to view submission history

• After filing, you can log back into D-MyTax at any time to see the status of your return.
• The system displays a history of all submissions, including the date and time of each filing.

Status shows ‘received’ or ‘under processing’

• Typically, the status will update to “received” immediately after successful submission.
• If the Revenue Department is reviewing your return, the status may show “under processing.”
• You can also download a PDF receipt of your filed return from the portal.

What this means: you don’t have to wait for a letter — the online portal gives you real-time confirmation.

2025 Tax Calendar: Key Deadlines

• September 1 – October 8, 2025: Mid-year tax filing (PND 94) for income earned Jan–Jun 2025 (Siam Legal (legal guide)).
• January – March 2026: Employers issue withholding tax certificates (50 Tavi) (TVC Thailand (tax guide)).
• March 1 – April 8, 2026: Online annual personal income tax filing (PND 90/91) for year 2025 (PwC Tax Summaries (global tax advisory)).
• March 31, 2026: Deadline for paper form submission (Pattaya Mail (local news)).

The pattern is clear: two filing seasons (mid-year and annual) with online ends always a few days after the paper deadline.

What’s Confirmed: Key Facts You Can Rely On

• Online filing for year 2025 opens March 1, 2026 (Thailand Revenue Department e-Filing (official portal)).
• Online filing deadline is April 8, 2026 (AustCham Thailand / HLB guide).
• PND 94 deadline for mid-year 2025 is October 8, 2025 (PwC Tax Summaries (global tax advisory)).
• Paper forms deadline is March 31, 2026 (Pattaya Mail (local news)).
• D-MyTax is the official filing portal (Revenue Department English e-Service (official portal)).

“The Revenue Department’s e-Filing system supports normal filings, amended filings within the filing period, and late filings that may trigger surcharges, penalties, and criminal fines.”

— Thailand Revenue Department e-Filing portal (official gov site)

“Annual personal income tax returns can be filed online through the Revenue Department’s e-Filing system or the D-MyTax platform until 8 April 2026.”

— HLB Thailand, via AustCham Thailand (practitioner guide)

For taxpayers in Thailand, the choice is straightforward: file online by April 8, 2026, or risk penalties. The Revenue Department’s systems are mature, and the auto-fill feature removes much of the manual work. Missing the deadline means a 0.5% monthly surcharge plus a potential 20% penalty on the tax due — a cost that adds up fast.

Frequently asked questions