Expenses for services received from other companies in Thailand should ideally be supported by a tax invoice for both Corporate
Income Tax (CIT) deduction and VAT input claims.

However, situations arise where only an ordinary receipt or no formal invoice is provided, particularly if the service provider is not VAT-registered or is a small business.

General Criteria CIT Deductibility

Tax deductibility is possible, but challenging. Requires strong alternative documentation to prove the expense is genuine and for business. Risk of disallowance is high.

A withholding tax certificate (P.N.D. 53) is required if the service falls under a category subject to WHT (e.g., professional fees, services, hire of work).

Documentation Needed For CIT Deduction

Ordinary receipt or company letterhead that must include company name, address, date, service description, and amount.
• Proof of payment (bank transfer slip, cheque stub, or internal cash voucher).
• Service agreement or contract.
• Evidence of service delivery: Reports, completed work, meeting minutes, emails.
• Withholding tax filing (P.N.D. 53) as an evidence of having fulfilled WHT obligations.

References
• Thai Revenue Code, Section 65 ter (3) (General expense deductibility)
• Thai Revenue Code, Section 70 bis (Withholding tax for juristic persons)
• Thai Revenue Code, Section 82/5 (Requirements for a tax invoice)
• Thai Revenue Code, Section 82/3 (Input VAT deduction conditions)
• Ministerial Regulations and Notifications of the Director-General relevant to specific types of services and WHT rates.