TL;DR:Issue a detailed invoice with currency, bank SWIFT/FCD details and VAT/WHT notes; register for VAT if turnover >1.8M THB, handle withholding tax rules, use an FCD/multi-currency account, and keep records. Consult a Thai accountant and the Thai Revenue Department.
Create a clear commercial invoice and set up payment channels, then comply with Thai tax rules. Include: your business/sole-proprietor name, Thai tax ID or passport, invoice number and date, client name and country, a precise description of services, currency, bank details (account name, IBAN/SWIFT or FCD account), payment terms and VAT/WHT treatment. Check tax obligations: register for VAT if annual taxable turnover exceeds 1.8 million THB; exported services may qualify as zero-rated VAT but need documentation. Determine withholding tax: Thai payers must deduct and remit WHT on certain service payments (rates depend on payer/recipient status and DTAs); if you’re a Thai resident you must report the income and claim any WHT credits. Use an FCD or multi-currency account for foreign receipts to reduce FX costs and provide clear remittance instructions. Keep full records and issue withholding tax certificates when required. Consult a Thai accountant for registration, VAT zero-rate rules, and WHT filings with the Thai Revenue Department.
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