2026 Filing Calendar

Thailand Tax Calendar 2026Every Deadline in One Place

PND.1, PP.30, PND.50, PND.51, and Social Security Fund contributions each run on a different clock. Miss one and you owe a 1.5% monthly surcharge plus penalties. Here is the full 2026 filing calendar for Thai-registered companies.

  • 12xMonthly WHT & VAT filings per year
  • 2xCorporate income tax filings (PND.51 + PND.50)
  • 1.5%Monthly surcharge on late payments
  • 150 daysWindow to file PND.50 after year-end

Filing ledger

Month-by-month 2026 filing calendar

Choose a period below to see what is due. Start with Monthly for the recurring stack, or open a fiscal window when you need PND.50, PND.51, or AGM.

Start here

Or jump to a month

Every month3 filings

  • PND.1 / PND.3 / PND.53
    Withholding tax on payments to employees/vendors
    7th (paper) / 15th (e-filing) of the following monthAll companies with employees or withholding-taxable payments
  • PP.30
    Value Added Tax return
    15th (paper) / 23rd (e-filing) of the following monthVAT-registered businesses (turnover over THB 1.8M/year)
  • SSO Form 1-10
    Social Security Fund contribution
    15th of the following monthAll companies with registered employees

Rhythm

Filing obligations grouped by frequency

A quick reference for building your internal compliance calendar.

Monthly

12× / year
  • PND.1: withholding tax on salaries
  • PND.3 / PND.53: withholding tax on vendor payments
  • PP.30: VAT return
  • SSO contribution: employer + employee social security
  • Nil returns when there was no activity that month

Mid-year

1× / year
  • PND.51: half-year corporate income tax estimate
  • Half-year board review of tax provisioning
  • Mid-year VAT input / output reconciliation
  • Cash plan for the PND.51 advance payment
  • Checkpoint toward PND.50 / AGM year-end windows

Annual

Year-end cluster
  • PND.50: annual corporate income tax return
  • PND.90 / PND.91: personal income tax returns
  • Audited financial statements
  • AGM and DBD financial statement filing
  • SSO annual reconciliation

Late filing

What late filing actually costs

Thai tax penalties compound quickly because the surcharge is monthly, not one-time. Consistent monthly filing discipline is the cheapest form of tax compliance.

  1. 1.5% surcharge per month (or part of a month) on unpaid tax, capped at the tax amount itself.

  2. Fixed fines of THB 200 to 2,000 for late submission of PND and PP forms, even if the tax due is zero.

  3. Criminal penalties are possible for VAT non-filing exceeding certain thresholds or repeated non-compliance.

  4. Late SSO contributions accrue a 2% monthly surcharge on the outstanding employer and employee portions.

  5. A late or missing PND.50 can trigger a Revenue Department desk audit, extending scrutiny well beyond the missed filing.

Questions

Before the next deadline

What is PND.1 and when is it due in Thailand?

PND.1 is the monthly withholding tax return for salaries and wages paid to employees. It is due by the 7th of the following month for paper filing or the 15th for e-filing via the Revenue Department's online system.

What is the difference between PND.50 and PND.51?

PND.51 is a half-year corporate income tax estimate and advance payment, filed within two months of the midpoint of your fiscal year. PND.50 is the final annual corporate income tax return, filed within 150 days of fiscal year-end, reconciling actual tax owed against the PND.51 advance payment.

Does every company need to file PP.30 (VAT) monthly?

Only VAT-registered businesses need to file PP.30. Registration is mandatory once annual turnover exceeds THB 1.8 million. VAT returns are due monthly regardless of whether you had VAT-able sales that month; a nil return is still required.

What happens if I miss the SSO contribution deadline?

Social Security Fund contributions are due by the 15th of the following month. Late payment triggers a 2% monthly surcharge on the outstanding amount for both employer and employee portions, and repeated lateness can trigger a Social Security Office audit.

Can I file Thailand taxes myself without an accountant?

Technically yes for straightforward cases, but most companies use an accounting provider because monthly WHT, VAT, and SSO filings each have separate government portals, and errors compound through the 1.5% monthly surcharge. Most foreign-owned companies outsource this from day one.

Never miss a Thailand filing deadline again

Settlr's accounting team manages your full filing calendar (PND.1, PP.30, PND.50/51, and SSO) with built-in reminders and fixed monthly pricing.

Talk to Our Tax TeamSee Pricing

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