How to Verify IRN on a GST Invoice

To verify an IRN on a GST invoice, scan the signed QR code with the official Verify QR Code app. If the supplier provides the signed invoice JSON, upload that file through Search > Verify Signed Invoice on the NIC e-Invoice 1 portal. This is the e-invoice verification portal, not the GST Common Portal at gst.gov.in. After verification, compare the returned supplier GSTIN, recipient GSTIN, invoice number, invoice date, invoice value, HSN, IRN, and IRN generation date with the supplier invoice before AP approval, booking, or payment.

IRN means Invoice Reference Number. It is the unique 64-character hash returned after an Invoice Registration Portal (IRP) accepts the invoice data. It is not the supplier's invoice or document number; that supplier-assigned number is one of the inputs used to generate the IRN.

The live GSTN E-Invoicing FAQs explain that the signed QR code embeds selected invoice particulars: supplier and recipient GSTIN, the supplier's invoice number and date, invoice value, line-item count, main-item HSN, the unique IRN, and the IRN generation date. The verification app checks the signed QR code before displaying those particulars. They are the AP reviewer's evidence that the invoice in hand matches data signed through the Indian e-invoicing system.

A successful scan does not mean the invoice is fully approved. It does not prove that the goods or services were received, that the PO or GRN matches, that the tax rate is correct, that the supplier is low-risk, or that input tax credit will survive every later GST condition. It only supports one control: the signed QR / IRN data on the invoice is valid for the embedded e-invoice details.

That control belongs early in the accounts payable flow. Once an invoice is booked, routed for approval, or scheduled for payment, correcting a bad GST e-invoice becomes harder. AP teams should perform the IRN and signed QR check at intake or before final approval, then hold any invoice where the verified data does not agree with the document.

Decide Whether the Invoice Should Carry IRN and Signed QR Details

Before treating a missing IRN as a failed invoice, AP should decide whether the invoice appears to fall under Indian GST e-invoicing requirements. Some incoming documents will clearly present themselves as GST e-invoices, with an IRN, a signed QR code, supplier GSTIN, recipient GSTIN, invoice number, invoice date, taxable value, GST values, and HSN details. Others may be regular tax invoices, debit notes, credit notes, or supplier documents where applicability needs confirmation.

This is an intake question, not a full legal analysis by the AP clerk. The practical test is whether the supplier and transaction appear to be in the e-invoicing regime and whether the invoice claims to be an e-invoice. If the document should carry IRN and signed QR details but does not, AP should not quietly book it. If the supplier's e-invoicing applicability is unclear, route the invoice to the tax team or ask the supplier to confirm before rejecting it.

For the regime-level background, keep a separate reference to India GST e-invoicing and IRN requirements. This AP control is narrower: identify whether this inbound supplier invoice needs IRN verification, then perform that verification before the invoice moves further into approval or payment.

Avoid mixing this check with every GST invoice-field requirement. Rule 46-style invoice particulars still matter, but IRN verification is about the authenticity of the e-invoice data and the signed QR code. The field review becomes relevant when those verified details are compared back to the invoice in hand.

Scan the QR Code or Verify the Signed Invoice, Then Compare the Returned Fields

The usual recipient route is to scan the signed QR code with the Verify QR Code app available under Help > Tools on the e-Invoice 1 portal. If the supplier provides the signed invoice JSON, Search > Verify Signed Invoice lets AP upload the .JSON file and check its digital signature and content. A typed IRN or acknowledgement number is not a substitute for either signed-data check. A successful verification is not the final goal; AP must compare the official result against the supplier invoice.

These identifiers are related, but they are not interchangeable:

Identifier	What it is	How AP should use it
Supplier invoice or document number	The number assigned by the supplier and used as an input when the IRN is generated.	Match it to the invoice number embedded in the signed QR code.
IRN	The unique 64-character hash returned by the IRP for the registered invoice.	Verify it through the signed QR code or signed invoice JSON, then compare it with the invoice.
Acknowledgement number (Ack No.)	A separate 15-digit processing reference returned by the IRP. There is no mandate to print it on the invoice.	Do not treat it as the IRN or as standalone proof that the recipient's invoice is authentic.
Signed QR code	The IRP-signed carrier of the IRN and selected invoice particulars.	Scan it with the official app to authenticate and read the embedded data.

If AP has only an acknowledgement number, ask the supplier for the e-invoice with its signed QR code or signed JSON and IRN, or retrieve the signed record through an authenticated IRP workflow available to the organisation. Do not approve an invoice on the acknowledgement number alone.

AP should compare these fields line by line:

• Supplier GSTIN
• Recipient GSTIN
• Supplier invoice number
• Invoice date
• Total invoice value
• Line-item count
• Main HSN
• IRN
• IRN generation date

An exact match supports that the invoice document aligns with the IRP-signed data for those embedded fields. It is especially important to match the supplier GSTIN, buyer GSTIN, invoice number, date, value, and IRN, because these are the fields that usually drive booking, vendor ledger posting, tax review, and later reconciliation.

A mismatch should stop automated booking or payment. If the PDF shows one invoice number or value but the QR result shows another, AP should not treat the scan as a pass merely because the QR code authenticated. The supplier may have sent the wrong PDF, altered the document after IRP generation, cancelled and reissued the invoice, or made a genuine data-entry error. Until that difference is resolved, the invoice is not ready for routine approval.

Classify Exceptions Before Releasing the Invoice

AP teams should classify IRN verification exceptions by the decision they require, not by how the error looked on screen.

Unreadable QR code: Try a clearer copy or rescan from the original PDF. If the QR code remains unreadable, ask the supplier for the correct e-invoice copy before approval. Do not manually rely on typed IRN text if the signed QR cannot be validated.

Failed QR authentication: Check whether the QR code was cropped, compressed, or copied into another document. If the code still fails in the verifier, hold the invoice and request a corrected document or tax-team review.

Field mismatch: Treat differences in GSTIN, invoice number, date, value, HSN, IRN, or IRN generation details as material until explained. A known supplier relationship is not enough to override a mismatch in the signed e-invoice data.

Missing IRN or signed QR where expected: Ask the supplier whether the transaction is in scope and, if it is, request a valid e-invoice. If applicability is uncertain, tax should decide whether the invoice can be processed or must be corrected.

Cancelled, unknown, or doubtful IRN: Use an authenticated IRP workflow available to the organisation where appropriate and retain the result. If the signed QR or signed invoice cannot be verified, ask the supplier for the correct signed e-invoice and hold payment. Do not rely on a typed IRN or acknowledgement number alone.

Supplier identity checks sit beside this control. If the exception raises doubt about the GSTIN itself, use a separate process for GSTIN verification for vendor invoices rather than trying to solve supplier registration, e-invoice authenticity, and payment approval in one step. The same separation applies to country-specific supplier checks, such as Norwegian organisasjonsnummer and MVA verification before payment.

The workpaper should show what was checked, what failed, who reviewed the exception, and what evidence supported the final decision. That record matters later if the invoice is questioned during audit, vendor dispute resolution, or tax review.

Treat IRN Verification as One Control, Not Full Invoice Approval

IRN and signed QR verification proves a narrow but important point: the invoice data embedded in the QR code has been authenticated against the e-invoicing system. It does not prove that the underlying supply happened, that the price is correct, that goods were received, that services were accepted, or that the GST rate and place-of-supply treatment are correct.

AP still needs the normal approval controls around the verified invoice. Match the invoice to the PO and GRN where those controls exist. Check for duplicate invoice numbers and duplicate values. Confirm that the approver has authority, payment terms are correct, and the supplier master data is current. Review the tax calculation where the invoice is material, unusual, or coded to a sensitive expense category.

For GST credit, verified e-invoice data supports the control environment but does not replace return-level matching. Finance and tax teams still need GSTR-2B and IMS reconciliation controls to confirm whether purchase data appears in the records used for ITC review. A clean QR scan is therefore a strong intake signal, not a final ITC conclusion.

Treating QR verification as full approval misses ordinary commercial issues; skipping it because other controls exist lets unauthenticated e-invoices through. IRN verification belongs as one mandatory control in the wider approval chain.

A Practical AP Checklist for IRN Verification

Use a short, repeatable control so the check is performed the same way across suppliers and reviewers.

1. Confirm whether the supplier invoice appears to be in scope for GST e-invoicing and should carry IRN and signed QR details.
2. Scan the signed QR code using the official Verify QR Code app, or upload the supplier's signed invoice JSON through Verify Signed Invoice on the e-Invoice 1 portal.
3. Compare the returned supplier GSTIN, recipient GSTIN, supplier invoice number, invoice date, invoice value, line-item count, main HSN, IRN, and IRN generation date against the invoice.
4. Classify any exception: unreadable QR, failed authentication, field mismatch, missing IRN, cancelled or unknown IRN, or uncertainty over supplier applicability.
5. Hold the invoice if the verified data does not match the invoice or the official tool does not validate it.
6. Ask the supplier for correction, reissue, or explanation where needed, and route material GST exceptions to tax review.
7. Complete the normal AP checks before release: PO or GRN match, duplicate review, tax calculation review, approval authority, payment terms, and supplier master-data checks.
8. Retain evidence of the verification result, the fields compared, exception notes, supplier response, and tax-team approval where relevant.

The core rule is direct: no supplier invoice should move to routine payment merely because it carries an IRN on the face of the document. AP should verify the signed data, compare it to the invoice, and hold the document when the official result does not support the invoice being processed.