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Why Businesses in Thailand Should Outsource Accounting, Bookkeeping, and Annual Compliance

Posted on 3 November 2026

QUICK ANSWER

Outsourcing covers every monthly and annual filing a Thai company owes and can cost about 60% less than a full-time senior accountant.

Running a company in Thailand means filing something almost every month. The Department of Business Development (DBD) counts more than 976,000 business entities that must prepare financial statements each year. Each limited company among them must keep proper accounting records, send tax returns to the Revenue Department and have its accounts audited, even in a year with no sales.

The rules also change often. This guide covers what every company must file and which tasks a provider can take over. It also compares the cost of outsourced accounting in Thailand with a full-time hire and explains how to choose a firm.

KEY TAKEAWAYS

Every Thai limited company, trading or dormant, must keep books, file its tax returns, and submit CPA-audited accounts each year.
With a 31 December year-end, the AGM falls by 30 April and the annual corporate income tax return around 30 May.
Late tax payments carry a 1.5% monthly surcharge, and late DBD filings can lead to fines for directors personally.
In Reliance Consulting’s example, outsourcing costs about 60% less than a senior accountant on THB 60,000 a month.
A provider can handle bookkeeping, tax filing, payroll, and year-end work. The statutory audit must come from an independent CPA.

Why Does Accounting Matter from Day One?

Accounting matters from day one because a Thai company’s legal duties start on the day it is registered. Under the Accounting Act B.E. 2543 (2000) and the Revenue Code, the company must:

Record every sale, purchase, and expense as accounting entries backed by invoices or receipts
Use a bookkeeper who meets the DBD’s qualification rules
Close its accounts at least once every 12 months and keep its books for at least five years
Have its yearly financial statements audited by an independent certified public accountant (CPA), then file them with the DBD and the Revenue Department

Thailand has no dormant status, so a company with no sales still files a full audited set. The accounts follow Thai Financial Reporting Standards set by the Federation of Accounting Professions (TFAC), which also licenses the external auditors who sign them off. Still setting up? Start with our guide on how to register a company in Thailand.

EVIDENCE: STRICTER RULES FOR ACCOUNTANTS

Hiring a qualified in-house accountant now takes more checking. Since 1 January 2026, anyone registering as an accountant with the DBD must first pass a 60-question online exam. Registered accountants must also complete 12 training hours a year and can serve no more than 100 business entities.

Source: DBD announcement of 25 November 2025, summarised by Forvis Mazars Thailand.

What it means: A company that hires in-house should check its accountant’s DBD registration every year.

What Are the Key Filing Deadlines for Thai Companies?

Thai companies file tax returns every month and a half-year corporate tax return in August. With a 31 December year-end, the audited accounts and the annual income tax return are due around 30 May. Good tax compliance comes down to meeting each of these dates.

Monthly Filings

Most monthly returns go to the Revenue Department. Withholding tax returns must now be filed online, and online filers currently get eight extra days.

Filing	Form	Who files	Paper deadline	Online deadline	Filed with
Withholding tax on salaries	PND.1	Employers	Online only	15th	Revenue Department
Withholding tax on payments to individuals and Thai companies	PND.3, PND.53	Companies making those payments	Online only	15th	Revenue Department
Withholding tax on payments to overseas payees	PND.54	Companies paying foreign recipients	7th of the next month	15th	Revenue Department
VAT	PP.30	VAT-registered companies	15th	23rd	Revenue Department
VAT on services bought from overseas	PP.36	Companies paying foreign service providers	7th	15th	Revenue Department
Social security	SPS 1–10	Employers	15th	15th, plus 7 working days when paying through the SSO’s e-Payment channel	Social Security Office
Employee Welfare Fund	SKL.3	Employers with 10 or more employees (staff covered by a provident fund are exempt)	15th	15th	Department of Labour Protection and Welfare

The eight-day online extension currently runs until 31 January 2027 under a Ministry of Finance notification. Withholding tax returns can only be filed on paper if the company sends the Revenue Department a letter explaining why it cannot file online.

Withholding tax rates vary with the type of payment and the payee, which makes errors common. Our guide to common withholding tax mistakes covers the usual ones, and our withholding tax services can handle the monthly filing.

Annual Compliance Timeline (31 December Year-End)

When	Obligation	Filed with
By 8 March (online only)	PND.1 Kor, the annual summary of withholding tax on salaries	Revenue Department
By 30 April	AGM to approve the audited financial statements	Held by the company (no filing)
Within 14 days of the AGM	List of shareholders (BOJ.5)	DBD
Within 1 month of the AGM	Audited financial statements, filed online in XBRL format	DBD
Within 150 days of year-end (about 30 May; 8 days later online)	PND.50 annual corporate income tax return, with the audited statements	Revenue Department
By 31 August (8 September online)	PND.51 half-year corporate income tax return	Revenue Department

KEY DEADLINE

A Thai company with a 31 December year-end must hold its AGM by 30 April and file audited accounts with the DBD within one month after it.

What Happens When a Deadline Is Missed?

Late filings get expensive quickly, and some fines fall on directors as individuals.

Missed or wrong filing	Penalty	Who pays
Tax paid late on any return	Surcharge of 1.5% per month (part of a month counts as a full month), capped at the tax due, plus a fine of up to THB 2,000 for filing late	Company
VAT return (PP.30) filed late	A further penalty of up to twice the VAT due. If the company files on its own before a tax officer raises the issue, this drops to 2–20%, depending on how late the return is	Company
Half-year profit on the PND.51 underestimated by more than 25% without good reason	Surcharge of 20% on the tax shortfall	Company
Social security contributions paid late	Surcharge of 2% per month on the amount due, capped at the contributions owed	Employer
AGM not held within 4 months of year-end	Fine of up to THB 20,000 for the company and up to THB 50,000 for directors	Company and directors
List of shareholders (BOJ.5) filed late	Fine of up to THB 10,000	Directors
Audited financial statements filed late with the DBD	Fine of up to THB 50,000 for the company and up to THB 50,000 for the managing director	Company and managing director

EVIDENCE: DIRECTORS CARRY PERSONAL LIABILITY

Missed DBD deadlines cost directors as well as the company. Under Section 40 of the Accounting Act, the managing director faces the same penalty as the company unless they can show they took no part in the breach. In practice, DBD settlements for a private limited company start at THB 1,000 each when a filing is up to two months late. They reach THB 6,000 each after four months.

Source: Juslaws & Consult and Khonsu Legal, citing the Accounting Act and DBD practice.

What it means: A provider that tracks AGM and filing dates protects the directors, too.

What Accounting Tasks Can Businesses in Thailand Outsource?

Almost every recurring task can go to an outside provider, from bookkeeping and tax returns to payroll and the year-end accounts. Two steps remain outside the provider’s role: an independent CPA performs the statutory audit, and the shareholders approve the accounts at the AGM.

In most accounting and tax packages, the services include the tasks below.

Task	How often	What the provider does	What the business still does
Bookkeeping and accounting entries	Daily to monthly	Records sales, purchases and expenses; reconciles bank accounts	Sends invoices, receipts and bank statements on time
VAT and withholding tax returns	Monthly	Prepares and files the PP.30, PP.36, PND.1, PND.3, PND.53 and PND.54	Approves and pays the tax due
Payroll, social security and Employee Welfare Fund	Monthly	Calculates pay, deductions and contributions; files with the Social Security Office and the Department of Labour Protection and Welfare	Confirms new hires, leavers and salary changes
Management reports	Monthly	Prepares the balance sheet, profit and loss statement, and receivables and payables ageing	Reviews the figures and makes decisions
Corporate income tax	Twice a year	Estimates profit and files the PND.51 and PND.50	Signs off the figures
Year-end financial statements	Yearly	Closes the books under TFRS for NPAEs and works with the external auditors	Appoints an independent CPA
AGM paperwork	Yearly	Drafts the minutes and files the BOJ.5 with the DBD	Holds the meeting

How Does Outsourced Accounting Work Month to Month?

A typical monthly cycle looks like this:

The business uploads invoices, receipts, and bank statements early in the month.
The provider records the entries, reconciles the bank accounts, and files the VAT and withholding tax returns.
Monthly reports arrive by mid-month.
At year-end, the provider closes the books, works with the auditor, and files with the Revenue Department and the DBD.

Payroll can be part of the same package, and our guide to payroll outsourcing in Thailand explains the options. For the audit itself, see our audit and assurance services.

QUICK ANSWER

Bookkeeping, tax returns, payroll and year-end closing can all be outsourced. Only the statutory audit must come from an independent CPA.

What Are the Benefits of Outsourcing Accounting Services in Thailand?

With professional accounting services, a business gets trained accountants who track Thai tax changes, file on time, and report every month. The fee is fixed, and headcount stays the same.

Lower Fixed Costs

An in-house accountant comes with a salary, a bonus, social security, paid leave, insurance, software and training costs. An outsourced team replaces all of these with one monthly fee for day-to-day accounting management, so finance costs are easier to predict.

Accountants Who Follow Rule Changes for You

Keeping up with Thai tax and business accounting rules takes real time. Recent changes include a higher social security wage ceiling of THB 17,500, which lifts the maximum monthly contribution to THB 875 each for the employer and the employee. Employee Welfare Fund contributions have also started. An accounting firm tracks changes like these across many clients at once.

Fewer Errors and On-Time Filings

A second reviewer catches mistakes before they reach the Revenue Department. That matters, because a wrong withholding tax rate or a half-year profit estimate set too low can trigger the surcharges shown in the penalty table above. At Reliance Consulting, a senior account manager checks every monthly report before it goes out.

Clearer Cash Flow and Financial Information

Monthly management reports show what the business earned, what it spent, and who still owes it money. Owners can see where cash is tied up and act before a slow month becomes a shortfall. Sorted records also make the year-end close faster.

Continuity When Staff Leave, and Room to Grow

A one-person finance team stops when that person is sick, on leave, or resigns. An outsourced team covers the gap. As volumes grow, the business moves up a package tier instead of hiring. Auditors are heavily booked from January to April, and a provider that starts the year-end close early makes the 30 April AGM easier to meet.

Stronger Protection for Financial Data

Payroll files and bank details contain personal data. Thailand’s Personal Data Protection Act (PDPA) has been fully in force since 1 June 2022, with administrative fines of up to THB 5 million. Ask any provider who can access your records and whether it will sign a data processing agreement.

Together, these benefits give owners back the hours spent on paperwork, time they can put into sales and customers instead.

Is It Cheaper to Outsource Accounting Than Hire an In-House Accountant?

For many small and mid-sized companies, yes. Reliance Consulting’s own example puts the saving at about 60% against a full-time senior accountant, once bonus, leave, insurance and social security are added to the salary.

Monthly cost (THB)	Senior accountant	Finance manager
Basic salary	60,000	150,000
Social security (5%, wage capped at THB 17,500)	875	875
One-month bonus, spread over 12 months	5,000	12,500
Cover for 12 days of annual leave	2,769	6,923
Medical and accident insurance	1,200	2,000
Total in-house cost	69,844	172,298
Reliance Consulting outsourced fee	28,000	70,000
Monthly saving	41,844	102,298
Yearly saving	502,128	1,227,576
Saving	60%	59%

Figures are Reliance Consulting’s illustrative example, updated for the current social security ceiling. Actual fees depend on transaction volume and scope, so ask for a quote based on your monthly numbers.

QUICK ANSWER

A full-time senior accountant on THB 60,000 costs about THB 69,844 a month in total. A comparable outsourced package costs THB 28,000.

What Costs Should You Ask About Before Signing?

Both options carry costs beyond the headline price. Ask about these before deciding:

Outsourced: the CPA audit fee (usually billed separately), charges above the transaction limit (THB 300 per extra transaction at Reliance Consulting) and any clean-up of past books

In-house: recruitment, software licences, yearly training to keep the accountant’s DBD registration active, and cover during leave or after a resignation

Outsourced vs In-House Accounting: Pros and Cons

Factor	Outsourced team	In-house accountant
Monthly cost	Fixed fee that rises with transaction volume	Salary plus about 15–16% in other employment costs (see the table above)
Cover during leave or turnover	A team fills the gap	Work stops until someone takes over
Rule changes	Tracked across many clients	Depends on one person’s training
Availability	Remote, with documents sent on a set schedule	On site, with questions answered on the spot
Knowledge of the business	Builds up over the first few months	Deep, from daily involvement
Best fit	New, small and foreign-owned companies, and BOI-promoted firms without a finance team	Companies with very high volumes or complex internal processes

Many larger companies combine both, with an in-house clerk for daily entries and an outside firm for tax filing and the year-end close. If you still keep your own books, see our accounting tips for small business owners.

How Do You Choose the Right Accounting Firm?

Choose an accounting firm in Thailand with DBD-registered bookkeepers, access to licensed CPAs, and experience with businesses like yours. Then check these six points:

Registered people: DBD-registered bookkeepers with current training, plus TFAC-licensed CPAs for the audit.
Relevant experience: a Thai limited company, a BOI-promoted company, and a branch office each report differently, so ask whether the firm already serves clients set up like yours.
Full scope: accounting and tax filings, payroll, social security, the Employee Welfare Fund, AGM minutes, and the BOJ.5.
Clear pricing: the monthly fee, the transaction limit, extra-transaction charges, and whether the audit is included.
Language and response times: reports in English and Thai, a named accountant, and agreed reply times.
Data handling: who sees your records, which software is used, and a data processing agreement under the PDPA.

At the first meeting, ask three things. Who reviews my monthly reports? What happens to my fee if transactions go above the limit? Who deals with the Revenue Department if my company is audited?

Outsource Accounting and Annual Compliance with Reliance Consulting

Monthly returns, a yearly audit cycle, and changing rules are easier to manage with a dedicated team. Reliance Consulting provides outsourced accounting in Thailand on fixed monthly packages, starting at THB 15,000 for up to 30 transactions.

Each client works with an English-speaking CPA, receives reports by the 15th of each month and has our team’s support during statutory audits. Reliance Consulting is a member of the Santa Fe Associates International (SFAI) network. Contact us to discuss your monthly volume and get a quote.

Frequently Asked Questions

Why do companies in Thailand outsource accounting?

Most do it to meet monthly and yearly filing duties without a full-time hire. An outsourced team tracks rule changes, files tax returns on time and sends monthly reports for a fixed fee. In Reliance Consulting’s cost example, that costs about 60% less than employing a senior accountant.

What accounting standards do companies in Thailand follow?

Thai companies follow Thai Financial Reporting Standards (TFRS), issued by the Federation of Accounting Professions. Most private companies use TFRS for NPAEs (revised 2022). Listed and other publicly accountable companies use full TFRS, which closely follows IFRS. See how Thailand’s accounting standards differ from IFRS for the details.

How much does outsourced accounting cost in Thailand?

Fees depend mainly on how many transactions a company records each month and which services it needs. Reliance Consulting’s fixed packages start at THB 15,000 a month for up to 30 transactions, with extra transactions at THB 300 each. The annual CPA audit is usually quoted separately.

Does a dormant company in Thailand still need audited accounts?

Yes. Thailand has no dormant status for companies. A company with no revenue still prepares financial statements, has them audited by a CPA, holds an AGM, and files with the DBD and the Revenue Department. If it is VAT-registered, it also files a nil PP.30 return every month.

Can my outsourced accountant also audit my company’s accounts?

No. The statutory audit must be signed by a TFAC-licensed CPA who is independent of the company, so the person who keeps your books cannot audit them. An outsourced provider can prepare the accounts and work with the auditor, while a separate CPA signs the audit opinion.

Does my company have to join the Employee Welfare Fund?

It does if it has 10 or more employees. Staff already covered by a qualifying provident fund are exempt. Employer and employee each contribute 0.25% of wages, paid to the Department of Labour Protection and Welfare by the 15th of the following month. Contributions began on 1 October 2026, and the rate is set to rise to 0.5% from 1 October 2031.

When does a Thai company have to register for VAT?

A company must register within 30 days of its annual turnover passing THB 1.8 million, using Form PP.01. The VAT rate is 7%, made up of 6.3% VAT and 0.7% local tax, and Royal Decree No. 807 keeps that rate until 30 September 2027.

Sources

Last updated: October 2026

Disclaimer: This article is general information based on the rules in force at the time of writing. It is not tax or legal advice. Rates, deadlines and penalties can change, so check with the Revenue Department, the DBD or a qualified adviser before acting.