Most foreign founders choose their first Thai accountant in a hurry, usually the week after the company is registered and the first VAT or payroll filing is due. That is the wrong time to choose well. This guide sets out what the law requires, what a reasonable fee looks like, and how to compare firms on the things that matter later. For the legal deadlines themselves, see our accounting and audit requirements guide.
What a Thai company legally needs#
Thai law separates the work into roles, and you need all of them from the first month:
| Role | Who can do it | What they do |
|---|---|---|
| Bookkeeper (ผู้ทำบัญชี) | An accountant with the qualifications set by the Department of Business Development (DBD), registered with the DBD | Keeps the books under the Accounting Act, prepares monthly records and the financial statements |
| Auditor | A Certified Public Accountant (CPA) licensed by the Federation of Accounting Professions (TFAC) | Signs the annual audit opinion. Must be independent of the bookkeeper |
| Tax filer | Usually the bookkeeping firm | Files PP.30 (VAT), PND.1, PND.3 and PND.53 (withholding tax), SSO contributions, and PND.50/51 |
There is no audit exemption for limited companies, even dormant ones. A company that skips the audit, the AGM or the DBD e-filing faces fines, and directors can be personally liable (DBD). The annual cycle is set out in our annual compliance calendar.
Typical fees in Bangkok#
Accounting fees in Bangkok are not regulated, and firms price very differently. The ranges below are those used in our existing guides and widely quoted by Bangkok firms. Treat them as a starting point for comparison, not a price list.
| Service | Small company (low volume) | Note |
|---|---|---|
| Monthly bookkeeping and tax filing | About 3,000–8,000 THB/month | Price rises with the number of invoices, employees and VAT |
| Annual CPA audit | About 15,000–40,000 THB | Larger or complex companies pay much more |
| Dormant company package | About 10,000–25,000 THB/year including the audit | Only for genuine nil activity |
| Payroll per employee | Often charged per head | Ask whether the SSO and PND.1 filings are included |
What moves the price:
- Volume. Most firms price by the number of documents a month (sales invoices, purchase invoices, bank transactions).
- VAT registration. A VAT-registered company has to file PP.30 every month and keep input and output tax reports, which adds work (VAT guide).
- Payroll. Each employee adds PND.1 withholding and SSO filings (payroll guide).
- BOI promotion. BOI companies have extra reporting, for example on the use of promoted machinery and incentives (BOI guide).
- Language. Monthly reports and email in English often cost more than Thai-only service.
Ten questions to ask before you sign#
- Who will do my books? A named person, or a pool? Is that person registered with the DBD as a bookkeeper?
- Who is the auditor? If the firm proposes an auditor, ask for the CPA's name and licence number and check it with TFAC. The auditor must be independent of the person keeping your books.
- What is included in the monthly fee? Get a list: VAT, withholding tax, SSO, PND.51 (half-year), PND.50 (annual), the DBD e-filing, the shareholder list (Bor Or Jor 5) and AGM minutes.
- What is the document limit? Ask what happens if you exceed it in a busy month.
- How do documents move? Photos by LINE, a shared folder, an accounting app, or paper collected monthly? Tax invoices often need to be originals or valid e-Tax invoices.
- What is the monthly deadline for my documents? Most firms need them in the first week of the month to file VAT and withholding tax by the 15th, or later if filed online.
- What reports will I get? At least a monthly profit and loss, a balance sheet and a VAT summary. Ask for a sample.
- Who pays penalties if the firm files late? The surcharge on late tax is 1.5% per month of the tax due, plus fines (Revenue Department). Ask for the firm's policy in writing.
- What happens when we leave? You should get the general ledger, the trial balance and all source documents back. Ask how long the handover takes.
- Can you handle the next step? If you plan to hire foreigners, register for VAT or apply for BOI promotion, ask whether the firm already serves clients like that.
Red flags#
- The same person keeps your books and signs your audit. This breaks the independence rule and makes the audit worthless.
- No written engagement letter. You need the scope, the fee and the deadlines on paper.
- "We file nil returns until you have revenue." Even a company with no income must keep books, have an audit and file. Nil filings are fine only if they reflect reality.
- Unusually low annual packages that "include everything". Ask what the audit fee is separately and who the auditor is.
- No access to your own records. You should always be able to get your ledgers.
- Paying the firm's tax bill into a personal account. Tax should be paid to the Revenue Department through e-filing or the bank, not to a staff member.
Small local firm, mid-size firm or international network?#
| Small local firm | Mid-size firm | International network | |
|---|---|---|---|
| Typical client | Thai SMEs, small foreign-owned companies | Foreign-owned SMEs, BOI companies | Subsidiaries of foreign groups |
| Price | Lowest | Middle | Highest |
| English | Varies a lot | Usually good | Usually strong |
| Strength | Price, flexibility | Mix of price and process | Group reporting, complex tax |
| Watch for | Key-person risk, documentation | Staff turnover | Junior staff on small accounts |
There is no single right answer. A company with ten invoices a month does not need a network firm. A company preparing consolidated reports for a parent abroad usually does.
Switching accountants#
You can change accountants at any time, but it is easiest after the year-end audit. To switch cleanly:
- Give notice under your engagement letter.
- Ask for the general ledger, the trial balance, the fixed asset register, filed tax returns and receipts, and all source documents.
- Give the new firm read access to your Revenue Department e-filing and SSO accounts, or reset the passwords.
- Confirm who files the next month's returns so nothing is filed twice or missed.
- If the auditor is changing too, the new auditor will need the prior year's audited statements.
Frequently asked questions#
How much does an accountant cost in Bangkok? For a small company, monthly bookkeeping and tax filing typically costs about 3,000–8,000 THB, and the annual audit about 15,000–40,000 THB. Volume, VAT, payroll and English reporting push the price up.
Do I need an auditor if my company had no revenue? Yes. Thai limited companies must have their annual financial statements audited by a CPA, even when dormant.
Can my bookkeeper also be my auditor? No. The auditor must be independent of the bookkeeping.
How do I check a CPA licence in Thailand? Ask for the CPA's name and licence number and check them with the Federation of Accounting Professions (tfac.or.th).
Can I do my own bookkeeping? Only if the person keeping the books meets the DBD bookkeeper qualifications and is registered. Most foreign founders use a firm.
What should my accountant send me every month? At least a profit and loss statement, a balance sheet, the VAT report if you are registered, and copies of the filed returns and payment receipts.
