Thai Corporate Income Tax | P.N.D.50 & P.N.D.51

Reconcile the accounting result to the tax result

Financial statements follow accounting rules. Corporate income tax requires a separate examination under the Revenue Code. Start with accounting profit or loss, document the tax adjustments and establish the applicable tax base before calculating the return.

Depreciation, non-business expenses, bad debts, donations and specific exemptions may require different treatment. A receipt alone does not prove deductibility. Conversely, absence of a VAT tax invoice does not by itself decide the corporate-income-tax treatment; examine the transaction, recipient and required evidence.

P.N.D.50 and P.N.D.51 are not interchangeable

For entities required to file P.N.D.50, the general annual deadline is 150 days from the accounting period end. The general interim filing period for P.N.D.51 is within 2 months after the first six months end. Establish the actual accounting dates and check current extensions rather than assuming every business has a December year-end.

Do not apply one estimated-profit method to every legal entity. Tax on net profits, other tax bases, specified business categories and short first or final accounting periods require a case-specific check. P.N.D.51 is neither half the year's sales nor a second annual financial-statement filing.

Where an annual profit estimate is required, retain the first-half results and documented assumptions for the remaining months. Consider actual contracts, seasonality and known costs. If the final result differs, review the reasons and relevant surcharge rules; a low estimate is not automatically protected from consequences.

Section 67 Bis excludes a company or juristic partnership whose first or final accounting period is less than 12 months from the interim requirement in that section. Confirm that the period actually qualifies; a short period for another reason should not be assumed exempt.

Build an evidence file before claiming deductions

• Entity details, accounting dates, business activities and evidence of any claimed promotion or exemption.
• Trial balance, general ledger, relevant statements, opening balances and adjustment schedules.
• Contracts, receipts, recipient identification and payment evidence for items requiring review.
• Fixed-asset and depreciation schedules and evidence for bad debts or donations, where relevant.
• Previously submitted P.N.D.50 and P.N.D.51, payment receipts and withholding certificates issued to the business.

Agree a secure document-sharing arrangement after the initial scope review. Do not send tax-account passwords, bank credentials or one-time codes through ordinary messages. Taking over a new period does not certify all of the previous accountant's filings.

Tax credits need matching records

Interim tax paid and qualifying tax withheld from the business's income can be considered against annual liability under the applicable rules. Reconcile taxpayer identity, income, period and amounts against certificates and accounting evidence. Tax withheld by the company from a supplier is not the company's own withholding credit.

Keep corporate-income-tax credits separate from VAT input tax. Do not reuse the same certificate across periods without establishing the proper treatment. Resolve incorrect certificates with the issuer. A refund request is subject to examination; it is not a promise of automatic repayment or a fixed processing time.

Losses and reduced rates require an eligibility check

A business with filing obligations may still have to submit a return when no tax is payable. Accounting loss is not necessarily tax loss. Review eligible loss amounts, their permitted life and amounts already used before carrying them forward. Losses cannot simply be kept indefinitely or transferred from another company.

Being described commercially as an SME does not establish eligibility for a reduced rate. Review paid-up capital, revenue and the rules applicable to the period. BOI or other specific relief needs supporting evidence and appropriate separation of the relevant activities; small size alone does not create a blanket tax exemption.

Approve the computation and retain separate filing evidence

Provide the authorised reviewer with accounting profit, adjustment schedules, the tax base and proposed credits, highlighting unresolved evidence. Specify who prepares, approves, submits and pays. Permission to prepare a return does not itself authorise bank access or payment execution.

Retain submission acceptance and payment receipts separately. A screenshot of a draft is not proof of completed filing. For an error found later, assess the impact on the previous return, financial statements and subsequent periods before correcting it. No assurance is given that a correction eliminates penalties or surcharges.

Request a quotation tied to the actual assignment

Tell our team the entity type, accounting period, transaction volume, previous provider, required returns and unresolved issues. Identify computation, credit review, submission, historical corrections and annual-accounts or audit coordination separately. Contact our team for a quotation rather than assuming that every associated task is included.

Questions from directors and overseas owners

Related existing services

Official references

• Revenue Department: corporate tax base, expense adjustments, credits and filing periods
• Revenue Code: Sections 65, 65 Bis, 65 Ter and 67 Bis–68

The English overview includes historical rate tables. Those tables are not used here to certify a current rate or a particular business's eligibility.