Tax Registration & Obligations

At a Glance

  • Who it's for: All Thai companies and foreign businesses operating in Thailand
  • Key taxes: Corporate income tax (20%), VAT (7%), withholding tax (various rates)
  • Registration timing: Within 60 days of company registration or business commencement
  • VAT threshold: ฿1.8 million annual turnover (mandatory registration above this amount)

Corporate Income Tax Registration

Tax ID Number Assignment¹

Automatic Assignment:

  • Tax ID number issued during company registration with DBD
  • Same 13-digit number used for all tax purposes
  • No separate application required for basic registration
  • Appears on business registration certificate

Additional Registrations:

  • VAT registration (separate process if required)
  • Withholding tax agent registration
  • Specific activity tax registrations
  • Branch or subsidiary registrations

Corporate Income Tax Rates¹

Standard Rates (2025):

  • 20% on net profits for companies with paid-up capital ≥฿5 million
  • 15% on first ฿300,000 profit for smaller companies
  • 20% on profits above ฿300,000 for smaller companies
  • 0% on dividends received from Thai companies (subject to conditions)

Special Rates:

  • 10% for newly established companies (first 3 years, with conditions)
  • Reduced rates for BOI-promoted companies
  • Various rates for specific industries (banking, insurance, etc.)

VAT Registration and Obligations

VAT Registration Requirements²

Mandatory Registration:

  • Annual turnover exceeds ฿1.8 million
  • Business activities subject to VAT
  • Import of goods or services
  • Request for voluntary registration below threshold

Registration Process:

  1. Submit VAT registration form (Por Por 01) to local Revenue Office
  2. Provide company registration documents
  3. Business license and activity permits
  4. Bank account opening documents
  5. Receive VAT registration certificate

VAT Rates and Applications²

Standard VAT Rate: 7%

  • Applied to most goods and services
  • Both domestic sales and imports
  • Some services have special calculation methods

Zero-Rated (0% VAT):

  • Exports of goods and services
  • International transportation
  • Goods in bonded warehouses
  • Some agricultural products

Exempt (No VAT):

  • Financial services (banking, insurance)
  • Medical and educational services
  • Residential property rentals
  • Some agricultural activities

VAT Filing and Payment²

Monthly Filing (Por Por 30):

  • Due by 15th of following month
  • Input VAT vs Output VAT reconciliation
  • Electronic filing through RD e-Filing system
  • Payment by bank transfer or at Revenue Office

Required Documentation:

  • Sales invoices and receipts
  • Purchase invoices with VAT
  • Import/export documentation
  • Bank statements and cash records

Withholding Tax Obligations

Withholding Tax Rates¹

Payments to Residents:

  • 5% on service fees to companies
  • 3% on service fees to individuals
  • 1% on goods purchases from unregistered suppliers
  • 10% on rental payments

Payments to Non-Residents:

  • 15% on service fees (or treaty rate if lower)
  • 10% on royalties (or treaty rate)
  • 25% on branch profits remittance
  • Various rates under double tax treaties

Filing Requirements

Monthly Returns (Por Ngor Dor 1):

  • Due by 7th of following month
  • List all payments subject to withholding
  • Submit withholding tax certificates to payees
  • Electronic filing available

E-Filing and Digital Services

Revenue Department e-Services¹

Online Services Available:

  • VAT registration and filing
  • Corporate income tax returns
  • Withholding tax returns
  • Payment processing
  • Account status checking

e-Filing Benefits:

  • 24/7 submission availability
  • Faster processing times
  • Automatic calculation features
  • Digital receipt and confirmation
  • Integration with accounting systems

Required Digital Infrastructure

Electronic Systems:

  • Thai-compliant accounting software
  • VAT invoice generation capability
  • Electronic payment systems
  • Digital document storage
  • Backup and security systems

Annual Tax Compliance

Corporate Income Tax Returns

Filing Deadline:

  • May 31st for calendar year companies
  • 150 days after fiscal year-end for other periods
  • Extension possible with advance payment

Required Documents:

  • Audited financial statements
  • Director and shareholder details
  • Related party transaction disclosures
  • Transfer pricing documentation (if applicable)
  • Supporting schedules and calculations

Tax Audit and Assessment

Audit Selection:

  • Risk-based selection by Revenue Department
  • Large transactions or unusual patterns
  • Industry-specific focus areas
  • Random selection process

Audit Process:

  • Advance notice (typically 15 days)
  • Document requests and interviews
  • On-site examination if required
  • Draft assessment and response period
  • Final assessment and appeal rights

Transfer Pricing and Documentation

Transfer Pricing Rules¹

Applicable Transactions:

  • Related party transactions ≥฿20 million annually
  • Transactions with companies in low-tax jurisdictions
  • Debt arrangements with related parties
  • Intellectual property licensing

Required Documentation:

  • Master file and local file preparation
  • Economic analysis and benchmarking
  • Country-by-country reporting (large MNEs)
  • Annual submission with tax return

Common Pitfalls to Avoid

Late VAT registration: Failing to register when turnover exceeds ฿1.8 million results in penalties and back-tax assessments.

Inadequate VAT invoicing: Using non-compliant tax invoices invalidates input VAT claims and creates audit risks.

Missing withholding obligations: Failing to withhold tax on payments to suppliers and service providers creates joint liability.

Poor record keeping: Inadequate documentation for VAT input claims and transfer pricing leads to tax adjustments.

Non-compliance with e-filing: Not using required electronic systems for large taxpayers creates filing penalties.

Tax Planning Strategies

Legitimate Tax Optimization

Structure Optimization:

  • Holding company structures for dividend exemptions
  • BOI promotion for tax holidays
  • Treaty network utilization for withholding reduction
  • Timing of income and expense recognition

Compliance Enhancement:

  • Robust transfer pricing policies
  • Regular tax health checks
  • Professional tax advisory relationships
  • Proactive Revenue Department engagement

Red Flags to Avoid

Aggressive Planning:

  • Artificial transactions without business substance
  • Excessive debt financing from related parties
  • Inappropriate transfer pricing methods
  • Non-arms-length related party transactions

Sources:

  1. Revenue Department - Tax laws, rates, and procedures
  2. Revenue Department VAT Guide - VAT registration and obligations
  3. RD e-Filing Portal - Electronic filing systems and services

Legal Disclaimer: This information is a summary of official guidance from Revenue Department sources. In case of discrepancy, the official source prevails. Tax rates and regulations change frequently—always verify current requirements on official RD websites and consult qualified tax advisors before making tax decisions.