Contributor
Santana Saksudhayakom
Senior Advisor, Transfer Pricing
What is an e–Tax Invoice?
An e–Tax Invoice (Electronic Tax Invoice) is a tax invoice prepared in digital format, replacing the traditional paper-based document.
The key objectives of adopting the e–Tax Invoice system are to:
Minimize issues related to paper-based document management and enhance convenience in storage, retrieval, and data exchange.
Support electronic transactions in line with the government’s digital economy policy, while promoting a modern and efficient business image.
Ensure the accuracy, authenticity, and verifiability of tax-related information.
Relevant Laws and Regulations
The implementation of e–Tax Invoices is governed by the following laws and standards:
Ministerial Regulation No. 384 (B.E. 2565) – issued under the Revenue Code concerning the preparation of documentary evidence through electronic means.
Electronic Transactions Act B.E. 2544 (2001) and its amendments (No. 2–4).
ICT Standard Recommendation No. 3-2560 – concerning electronic messages for trade in goods and services.
Type of e-Tax Invoices
The Revenue Department recognizes two main types of e–Tax Invoices:
1. e–Tax Invoice & e–Receipt
Suitable for businesses of all sizes (no income limitation).
Documents can be created in PDF, PDF/A-3, or XML format.
Must include a Digital Signature and an Electronic Certificate.
Data can be submitted to the Revenue Department through any of the following channels:
Web Upload – upload XML files directly to the Revenue Department via etax.rd.go.th.
Host to Host – for large enterprises (at least 500,000 documents per month) under the supervision of the Large Business Tax Administration Office. Data exchange must follow the ebXML standard, and prior approval is required.
Service Provider – submission via an authorized electronic data transfer provider, approved by the Revenue Department. This option is ideal for businesses that prefer not to develop or maintain their own system.
2. e–Tax Invoice by Email (e–Tax Invoice by Time Stamp)
Designed for small businesses with annual revenue not exceeding THB 30 million.
Documents can be created in PDF/A-3 or XML format.
Verification is conducted through a Time Stamp issued by the Electronic Transactions Development Agency (ETDA).
The system automatically transmits the data to the Revenue Department.
Verification and Authentication
To ensure the validity and legal recognition of e–Tax Invoices and e–Receipts, the system requires verification of the issuer’s identity and the accuracy of the document.
This process relies on two key technologies:
Electronic Certificate (Certification Authority – CA):
Acts as a digital identification card for the business. It is issued by a trusted electronic certification authority (a list of certified providers is available on the Revenue Department’s website).Digital Signature:
Functions like a handwritten signature that verifies the document’s authenticity and confirms that it was issued by the authorized taxpayer.
Comparison Summary
Item | e-Tax Invoice & e-Receipt | e-Tax Invoice by Email |
Business Size | All sizes | Small businesses (annual revenue ≤ THB 30 million) |
File Format | PDF, PDF/A-3, XML | PDF/A-3 + XML |
Verification Method | Digital Signature + CA | Time Stamp (ETDA) |
Submission Channel | Web, Host to Host, or Service Provider | Email only |
Submission to Revenue Department | Submitted manually by taxpayer | Automatically submitted by the system |
Conclusion
At present, the Revenue Department has not yet made the use of e–Tax Invoices mandatory.
Participation in the e–Tax Invoice system remains voluntary.
Furthermore, businesses that adopt the e–Tax Invoice system are not required to issue all invoices electronically—traditional paper invoices may still be used in parallel.
