What are the LHDN Unique Identification Number (UIN) and cryptographic QR code?
The LHDN Unique Identification Number (UIN) is a system-generated identifier returned by the LHDN CTC platform after it successfully validates a submitted e-invoice. The cryptographic QR code is a machine-readable visual representation embedded in the validated e-invoice, encoding the UIN and key transaction data. Under Malaysian law, an e-invoice is not legally valid until it carries a LHDN-issued UIN and QR code.
Why is the UIN and QR code legally significant?
Under Section 134A of the Income Tax Act 1967 and LHDN's e-Invoice Guidelines, an invoice submitted for CTC validation becomes legally valid only upon receipt of the LHDN-issued UIN and QR code. This means an invoice generated by the supplier's ERP but not yet cleared by LHDN has no legal standing as a tax document. Buyers cannot claim corporate tax deductions or input tax credits on the basis of an uncleared invoice.
How can the QR code be verified?
The cryptographic QR code can be scanned to retrieve the UIN and cross-reference it against the LHDN MyInvois system. This allows buyers, auditors, and tax authorities to instantly verify that an invoice was issued by the stated supplier, cleared by LHDN, and that the key fields have not been altered after clearance. The cryptographic binding between the QR code and the invoice data makes post-clearance tampering detectable.
Frequently Asked Questions
- How quickly does LHDN issue the UIN after submission?
- LHDN issues the UIN in near real-time following successful validation via API. The validation process checks the submitted XML against mandatory field requirements, TIN validity, mathematical totals, and business rule conformance. If validation fails, LHDN returns an error code rather than a UIN, and the submission must be corrected and resubmitted.
- Can the QR code be separated from the invoice document?
- The QR code must be included in the e-invoice document delivered to the buyer as specified in LHDN's technical guidelines. A buyer-received document without the QR code is not a complete, LHDN-cleared e-invoice.
Related Concepts
- What is Malaysia's LHDN 72-hour e-invoice cancellation and rejection window?
- What are Malaysia's self-billing e-invoice requirements for foreign supplier transactions?
- What is Section 134A of the Income Tax Act 1967 and how does it underpin Malaysian e-invoicing?
- What is the IRP in India's e-invoicing system?
- What is the difference between the LHDN API and the MyInvois Portal for e-invoice submission?