BUSINESS IN THAILAND / RESOURCE
A useful compliance calendar identifies the obligation, accounting period, due date, preparer, approver and proof of completion. It should reflect your company’s registrations and financial year rather than a generic list of dates. Use the baselines below to organise the work, then confirm the current authority calendar and applicable filing method.
Information reviewed 13 November 2026 · Pimaccounting
Monthly tax planning baselines
On smaller screens, scroll the table sideways to see all columns.
| Obligation | Ordinary baseline | Before treating it as complete |
|---|---|---|
| PND 1, 2, 3, 53 and 54 where applicable; PP36 | Normally the 7th of the following month for ordinary filing; check holidays and the applicable online timetable | Reconcile underlying transactions, review the return, retain acceptance and payment proof |
| PP30 VAT return; PT40 specific business tax where applicable | Normally the 15th of the following month for ordinary filing; online dates can differ | Reconcile the relevant tax report and account for adjustments |
| Social security contributions | Use the SSO timetable and current return instructions for the relevant employer and period | Reconcile the employee list, wage base, contribution return and payment |
These are planning baselines, not universal extensions or an assessment of which forms your business must file. The Revenue Department calendar identifies the month’s tax dates. SSO contribution instructions cover a separate agency process. Do not assume a Revenue Department online extension applies to social security.
Verified example: November 2026
The official November 2026 tax calendar gives the following dates. This dated example shows why channel and public holidays matter; check the current calendar for later months.
On smaller screens, scroll the table sideways to see all columns.
| Due date in November 2026 | Channel | Forms listed |
|---|---|---|
| 9 November | Ordinary filing; 7 November falls on a holiday | PND1, PND2, PND3, PND53, PND54 and PP36 |
| 16 November | Internet filing | PND1, PND2, PND3, PND53, PND54 and PP36 |
| 16 November | Ordinary filing; 15 November falls on a holiday | PP30 and PT40 |
| 23 November | Internet filing | PP30 and PT40 |
Check the return period, eligibility for the relevant channel and the payment procedure. Filing a return and settling the tax are distinct actions. Retain both confirmations and investigate a failed or pending payment before the cutoff.
Build annual deadlines from the company’s year-end
On smaller screens, scroll the table sideways to see all columns.
| Task | Planning rule | Dependencies |
|---|---|---|
| Annual corporate income tax return, PND50 | Within 150 days from the end of the accounting period | Closed accounts, tax computation, review and payment |
| Half-year corporate income tax return, PND51 | Within two months after the first six months of the accounting period, where applicable | Forecast or applicable calculation basis, adjustments and tax review |
| Private company annual accounts approval | Financial statements are submitted for approval at the general meeting within four months after year-end | Accounts preparation, auditor work and meeting arrangements |
| DBD financial-statement submission | Within one month from the date of approval by the general meeting | Approved statements and the required electronic filing documents |
| Annual BOJ5 shareholder list | Within 14 days after the ordinary general meeting | Company shareholder records reconciled to the list |
Sources: Revenue Department corporate filing guidance, DBD business duties and financial-statement timetable and DBD shareholder-record guidance. The table concerns the stated entity and obligations; first or shortened periods, other entity types and specific extensions require separate review. A non-calendar year-end changes the dates.
Add event-driven obligations
- A new activity, turnover change or change in the tax status of supplies may require a VAT review.
- Moving an office or opening a branch can require notifications before the move as well as changes afterwards.
- A change of director, signing authority or capital can trigger a registration timetable tied to the actual decision.
- Hiring or terminating employees changes payroll and social-security records. Foreign staff require separate immigration and work-authorisation planning.
- BOI-promoted projects have certificate-specific conditions and reporting duties.
Use the company administration guides and immigration extension guide to create separate event trackers. Do not compress every deadline into the monthly accounting cycle.
Work backwards from the authority deadline
Choose internal collection, preparation, review and payment dates that leave time to resolve missing evidence. For example, the finance team can agree a document cutoff, an exception review and a director approval window before the filing date. These internal dates are service arrangements, not statutory deadlines.
On smaller screens, scroll the table sideways to see all columns.
| Calendar field | Why it matters |
|---|---|
| Period and entity | Prevents filing for the wrong company or month |
| Source and date checked | Shows which official instruction informed the deadline |
| Preparer and approver | Makes responsibility visible |
| Filing and payment status | Prevents a submission from being confused with settlement |
| Receipt reference and location | Makes completion retrievable |
| Exception and next action | Keeps unresolved items in view |
Use the compliance planning worksheet to record these fields. Review the tracker whenever an authority notice, registration or financial year changes.
If a deadline has been missed
Identify the exact entity, form and period; check what was submitted and paid; preserve notices and receipts; and have the position reviewed promptly. Do not submit a duplicate return simply because the confirmation is missing. Corrections, late submissions, surcharges and penalties depend on the actual obligation and facts.
The catch-up bookkeeping guide explains how to separate reconstruction of accounts from correction of tax filings. A clear status schedule helps the accountant prioritise the work and explain the remaining exposure.
Frequently asked questions
Does electronic filing always give eight extra days?
Do not assume a permanent extension. Check the current official calendar, eligibility, form, channel and payment requirements for the relevant period.
Does every Thai company use a 31 December year-end?
No. Use the company’s actual accounting period. Annual deadlines must be calculated from that period and the applicable rules.
Is a filing receipt enough to prove tax was paid?
No. Keep the filing acceptance and the payment confirmation, and reconcile them to the correct return and period.
Does the tax calendar include immigration and social security?
The Revenue Department calendar covers its listed tax obligations. Social security, DBD and immigration require their own checks and trackers.
Official references and further reading
- Revenue Department — current tax filing calendar
- Revenue Department — November 2026 tax filing calendar
- Revenue Department — corporate income tax filing
- DBD — duties of registered businesses
- DBD — shareholder registers, share certificates and annual shareholder-list filing (Thai)
- Social Security Office — contribution return and wage-base instructions effective 2026
Reference review: 13 November 2026. Read current legislation, authority notices and case-specific requirements alongside this practical guide. Older manuals may contain superseded filing channels or rates. Service scope, professional fees, government charges and third-party costs should be confirmed separately.
Discuss your company’s next step
Tell us your activity, company stage and the records or decisions you need help with. We can discuss the appropriate accounting work and any specialist coordination, with deliverables and fees agreed before work starts.
Request a consultationRelated insights
View all articles
Thai Accounting for Income Tax Filing and Compliance
The Benefits of Pimaccounting’s Digital Solutions for Bookkeeping and Tax Filing
Carbon Accounting and the EU CBAM Ripple Effect: The New Frontier of Tax Advisory for Thai Businesses
Why Professional Accounting and Tax Advisory Services Are Essential in Thailand
Significant Changes in Thai Personal Income Tax for Foreign-Sourced Income: Implications for Individuals and Accounting Firms
Tax Management Solutions: The Crucial Role of Accounting Services
Why Every Business Needs Accounting Services: Simplifying Tax and Financial Management
How Accounting Firms Safeguard Your Business with Expert Tax Services
