Accounting Firm Thailand | Bookkeeping, Tax, Payroll and Audit

The duty starts on the date of company registration, not on the date of first revenue. The company must appoint a qualified bookkeeper, retain the supporting documents behind every entry, close the financial statements for each accounting period, have them audited by a licensed CPA, and file them with the Department of Business Development along with the tax returns due to the Revenue Department. Even a period with no trading activity still requires filing.

The monthly core is recording transactions from source documents, reconciling bank accounts, preparing and filing withholding tax, maintaining input and output VAT reports and filing the VAT return if registered, running payroll with social security submissions, and producing a management summary of the company’s position. The real quality marker is whether every source document is filed and traceable, not simply that the returns were submitted before the deadline.

A business whose VAT-liable turnover from goods or services exceeds the threshold set in the Revenue Code must apply for registration within the prescribed period. Some businesses also register voluntarily before reaching it — for example when customers require tax invoices, or when start-up investment generates substantial input VAT. Check the current threshold and the exemption categories with the Revenue Department first, because the exempt activities have detailed conditions.

A corporate payer must deduct withholding tax when paying the categories of income specified by law — service fees, hire of work, rent, professional fees and advertising among them — at rates that differ by income type and by the recipient’s status. The payer issues a withholding tax certificate to the recipient and remits the return by the Revenue Department’s deadline. The frequent error is applying the wrong rate after misclassifying the income, so describe the work precisely in the contract.

Limited companies and registered partnerships falling within the statutory conditions must have their financial statements audited and opined on by a licensed CPA before shareholder approval and submission to the Department of Business Development. What makes an audit run smoothly is closing the books monthly rather than at year end, keeping contracts and tax invoices complete, reconciling inventory and fixed assets, and being able to explain related-party transactions with documentation.

The recurring problems are late employer and employee registration, computing the contribution base from an incomplete definition of wages, confusing wages with exempt benefits, deducting personal income tax that does not match the allowances an employee declared, and keeping payment evidence that cannot be traced back. The structural fix is a written wage and benefit structure, with every payment tied to an approval document that an auditor or officer can follow.

Yes, provided the handover is complete enough that the accounting history has no gap. Ask the outgoing firm for the accounting data file and chart of accounts, the latest trial balance, receivable, payable and inventory detail, the fixed asset register, copies of filed tax returns with payment evidence, and all original documents. Then update the registered bookkeeper with the relevant authority and reconcile the opening balances before new entries are posted.

The core accounting and tax duties are the same as for a Thai-owned company, with additional layers: evidencing the source of invested funds, documenting transactions with overseas affiliates, withholding tax and double tax treaty treatment on outbound payments, and any conditions attached to a business licence or an investment promotion. Design the supporting documentation for those items at the start of the year rather than assembling it retroactively at closing.

Both the accounting legislation and the Revenue Code set retention periods, and in practice you should follow the longest one that applies to your business. Retain the books, the documents supporting each entry, tax invoices, filed returns with payment evidence, contracts and payroll records. If you store them electronically, make sure the archive can be retrieved in full and matches the originals when an officer asks to inspect it.

Check that the bookkeeper meets the statutory qualification and registration requirements. Ask who personally handles your file, get a written scope stating what is and is not included, clarify how documents are submitted and how often you receive reports, confirm you can access your own accounting data at any time, and ask how errors or an audit enquiry are handled. A warning sign is any promise about a tax outcome made before your documents have been seen.