Accounting & Tax Outsourcing Services

Accounting and tax outsourcing in Thailand means engaging a professional firm to manage your finance and tax functions end to end. Z&X goes beyond bookkeeping and tax filing to help you build a well-structured, efficient and sustainable financial management system. Key benefits include:

· Managed compliance: Dedicated handling of statutory processes such as bookkeeping, tax filing, personal income tax and social security filings, together with support for the annual statutory audit, helping you meet Thai tax requirements.

· Greater efficiency: Frees up internal resources and avoids errors caused by language barriers or unfamiliarity with local rules, so management can focus on the core business.

· Risk mitigation: Real-time tracking of regulatory changes and support during tax audits, serving as your external line of defence in finance.

Thailand's statutory accounting and tax calendar is demanding: VAT, withholding tax and personal income tax are filed monthly, corporate income tax is prepaid at mid-year and settled annually, and accounting documents must meet Thai invoicing rules and withstand Revenue Department audits. Chinese enterprises in Thailand commonly face language barriers, non-compliant documents, inconsistent Chinese and Thai reporting bases and difficulty aligning with headquarters reporting.

Through a model built on a dedicated team, direct Chinese-language communication and confirmation before filing, Z&X turns day-to-day finance and tax work into a predictable, traceable and well-documented standard process.

· Monthly bookkeeping and reporting: Preparation of journal vouchers, posting to ledgers and month-end close, delivering the balance sheet, income statement, general ledger, subsidiary ledgers and trial balance.

· Monthly tax filings: Statutory filings including VAT (P.P.30), withholding tax (P.N.D.3 / P.N.D.53) and employee personal income tax (P.N.D.1).

· Corporate income tax: Half-year prepayment (P.N.D.51) and annual return (P.N.D.50).

· Payroll, personal income tax and social security: Social security filings, withholding tax forms and certificates, salary withholding tax certificates, annual personal income tax summary (P.N.D.1K), individual annual income tax returns (P.N.D.90 / 91) and annual payroll reports.

· Annual financial statements: Year-end close and preparation of annual financial statements, with support for the statutory audit.

· Expedited reporting: Priority preparation and delivery of financial statements when urgently needed.

· Internal finance management: Management of Chinese and Thai documents, management accounts, monthly reporting and financial analysis.

· VAT refund applications: Assistance with VAT refund applications.

· Tax registration and changes: Assistance with tax registration and related changes.

· Transition from another provider: We help organise handover documents from your previous provider and issue an Accounting Health Check report before formally commencing monthly services.

For how the service works month by month, and how we handle factory book setup, BOI separate accounts and head office reporting, see the Finance and Tax Solution for Chinese Manufacturers in Thailand.

Each engagement is staffed by a dedicated team with a single point of contact and clearly defined roles. A Chinese project manager reports in Chinese throughout, delivering results directly to management.

Newly established and operating Chinese enterprises in Thailand (both BOI and non-BOI), group subsidiaries that need Chinese-language support and headquarters consolidation, as well as SMEs, foreign representative offices and start-ups in Thailand without a full-time finance team that want well-kept books and compliant filings at a manageable cost.

Beyond day-to-day accounting and tax outsourcing, Z&X also offers BOI management, finance and tax compliance, Tax Health Check, Financial Systems and Governance, investment structuring, specialised training and an annual finance and tax advisory retainer (Annual Finance & Tax Advisory Retainer). Statutory audits, specialised BOI services, Transfer Pricing and strategic advisory are separate engagements, scoped to each company's needs.

The Thailand Company Annual Tax & Compliance Calendar puts the fixed monthly filings (withholding tax, VAT, social security and more, each reporting the previous month), the half-year and annual deadlines on a full-year timeline, and the three things that most often go wrong onto two printable pages.

Free download: Thailand Company Annual Tax & Compliance Calendar (PDF, 2 pages)

Not sure which filings apply to your company, or whether any have been missed? Book an accounting and tax consultation →

The following services can be combined with this one; see each page for details:

· Financial Systems and Governance: financial policies, internal controls and management reporting for Thai subsidiaries

· ERP Finance System Implementation Advisory: finance system selection, go-live and alignment of Chinese and Thai reporting

· Which taxes does a Thai company file each month and each year, and what are the deadlines?

· If the company has not started trading and has no income, does it still need bookkeeping, tax filings and an audit?

· Our books were not kept properly and are a mess. How do we catch up?

· What is the difference between Sino‑Thailand dual‑track fiscal and tax services and ordinary local bookkeeping agency services?

· What documents are usually required for Chinese enterprises investing in Thailand for monthly bookkeeping and tax filing?

· When should VAT (PP.20) registration be completed, and what is its typical processing timeframe?

· Latest Policy from the Revenue Department of Thailand: Incentives for E‑Invoices and E‑Withholding Tax Extended to End‑2027, With Withholding Tax Rates for Thai‑based Enterprises as Low as 1%

· When a Chinese enterprise investing in Thailand pays service fees or technology royalties to its China headquarters, what taxes need to be declared in Thailand?

· How can the Thai company connect with the Chinese headquarters that uses Kingdee or UFIDA accounting software?

· How can Chinese enterprises find a suitable financial and tax service provider in Thailand?

· Why do the qualifications of Thai accounting and audit firms determine the capability boundary of financial and tax service providers?

Want advice tailored to your company? Book an accounting and tax outsourcing consultation →

Z&X provides monthly bookkeeping and tax filing for Chinese-invested companies in Thailand. Some of our published articles and reminders:

· Urgent reminder from a year ago: Are your Thai accounts still a mess?

· Annual compliance countdown: accounting backlog is triggering audit risks

· Countdown to Closing Accounts in 2025: Chain Risks and Response Strategies for Financial Backlogs in Thailand

· Thai accounting agency: Why is a team of accountants proficient in Chinese and Thai finance and taxation the key to success?

· Our licenses and certificates: three licensed firms in China and Thailand

Want to know whether your books and filings are compliant? Book an accounting and tax outsourcing consultation →

Articles from our Thailand Investment Guide related to this service:

· How to Build a Compliant Finance and Tax System After Registering a Company in Thailand

· Thailand Tax Compliance Guide: Key Points and Common Mistakes in Business Document Management

· The Hidden Costs Many Companies Overlook: A Complete Guide to Thailand's Less Common Taxes

· BOI After Approval (3): Tax Requirements — Exemption Does Not Mean No Tax Obligations, and 90% Get It Wrong

View all guide articles →