Thai Company Annual Audit Checklist: What You Must Submit

If you run a company registered in Thailand, annual audited financial statements are not optional. They are a legal requirement under the Accounting Act and the Civil and Commercial Code, and missing deadlines or submitting incomplete documents can result in fines, penalties, and complications with the Revenue Department. Whether you are managing a small foreign-owned company in Koh Samui or a growing local business, understanding exactly what you need to prepare and submit each year will save you significant stress. This checklist covers the core requirements so you know where you stand.

Understand Who Must Comply

Every juristic entity registered in Thailand is required to have its accounts audited annually by a licensed Certified Public Accountant (CPA). This includes limited companies, registered partnerships, and branches of foreign companies. There are no exemptions based on company size or revenue level. Even if your company had zero transactions during the year, you are still required to close the books, prepare financial statements, have them audited, and file them with the relevant authorities. Dormant companies are a common area where directors assume nothing needs to be done. That assumption is incorrect and often leads to accumulated penalties.

Checklist Item 1: Close Your Books for the Accounting Period

Your accounting period is typically 12 months and ends on 31 December for most Thai companies, though a different year-end is possible if approved. Within three months of your year-end, your financial statements must be approved by shareholders at an Annual General Meeting (AGM). Before you can do any of that, your bookkeeping must be complete and accurate. Make sure all bank statements are reconciled, all invoices and receipts are accounted for, VAT returns match your records, withholding tax filings are consistent with payments made, and payroll records are in order. Gaps in your bookkeeping at this stage will delay your audit and push everything back.

Checklist Item 2: Engage a Licensed CPA Early

Thai law requires that your financial statements are audited by a CPA who holds a Thai licence. You cannot use an unlicensed accountant or an overseas auditor for this purpose. The auditor will review your records, request supporting documents, and issue an audit report expressing their opinion on whether your financial statements present a true and fair view. Engaging your auditor early is important because CPAs have limited capacity during peak filing periods, particularly between January and May. If you leave this until the last minute, you may struggle to find an available auditor, or you may rush the process and introduce errors. Share your complete records with your auditor as soon as your year-end closes.

Checklist Item 3: Prepare the Required Financial Statements

The financial statements you submit must include a balance sheet, a profit and loss statement, notes to the financial statements, and a statement of changes in equity if applicable. These must be prepared in Thai baht and in the Thai language, or bilingual format. They must follow Thai Financial Reporting Standards (TFRS). The director of the company is required to sign the financial statements, confirming they have been prepared correctly. If you have a foreign director who is not based in Thailand, you need to plan ahead for obtaining their signature, as this is a step that is frequently overlooked and causes last-minute delays.

Checklist Item 4: Hold Your AGM and Approve the Statements

Once the audit is complete, you must hold an Annual General Meeting of shareholders to formally approve the audited financial statements. For most Thai companies, this must happen within four months of the financial year-end, meaning by 30 April for companies with a 31 December year-end. The AGM must be properly documented with minutes that record attendance, the agenda, and the resolution to approve the financial statements. These minutes will be needed when you file with the Department of Business Development (DBD). Keep the original minutes on file and ensure they are signed correctly. Many small companies treat the AGM as a formality, but the documentation still needs to be done properly.

Checklist Item 5: Submit to the DBD and the Revenue Department

There are two separate filing obligations you must complete. First, you must submit your audited financial statements to the Department of Business Development (DBD) under the Ministry of Commerce. This must be done within one month of the AGM, which in practice means by 31 May for companies with a 31 December year-end. You will file online through the DBD e-Filing system. Second, you must submit your corporate income tax return (Por Ngor Dor 50) to the Revenue Department. This is also due within 150 days of your financial year-end, so by 31 May if your year-end is 31 December. If you file online, the Revenue Department typically grants an additional eight-day extension. Both filings must be consistent with each other. Discrepancies between what you file with the DBD and what you report to the Revenue Department will attract scrutiny.

What Happens If You Miss the Deadlines

Missing your filing deadlines results in fines. For late DBD submission, the directors and the company can each face monetary penalties. For late corporate tax filing, surcharges and penalties are applied on top of any tax owed. Repeated failures to file can result in the Revenue Department conducting a tax audit or assessment, which may result in significantly higher tax liability based on estimated figures rather than your actual accounts. Companies that fail to file for multiple years can also be flagged for potential strike-off proceedings. Beyond the financial cost, non-compliance creates complications if you need to apply for work permits, renew business licences, or demonstrate good standing to partners or banks.

How to Stay Ahead Each Year

The most effective way to manage this process is to treat it as a year-round responsibility rather than something you deal with in April and May. Keep your bookkeeping current throughout the year so there is no backlog when your year-end arrives. Maintain organised records of invoices, contracts, bank statements, and tax filings. Confirm your auditor appointment well before year-end. Brief your director on any documents they will need to sign and when. If your company has foreign shareholders or directors, factor in additional time for communication and signatures. Working with an accounting firm that understands the full compliance cycle means these deadlines are tracked on your behalf and you are not left scrambling at the last moment.