GST number / GSTIN
The 15-character GSTIN identifies a GST registration. Use the correct supplier registration and the buyer’s GSTIN where applicable—not just a company name that looks right.
Check a GST numberFrom business identity to invoice identityE-invoices,
E-invoices,
from GSTIN to IRN.
A GST number identifies the registration. An e-invoice connects that identity to a reported transaction. Follow the journey without getting lost in the abbreviations.
Follow the invoice journey01 / Start with the identifiersWhich registration? Which business document? Which registered invoice?
One transaction. Three distinct references.
Keep the registration, your document number and the portal reference separate. Each helps you answer a different question.
Invoice number
Your business assigns the document number in its billing system. Keep it consistent across the invoice, reporting record and accounts so a customer query can be traced without confusion.
Invoice Reference Number
The IRN identifies the invoice registered through the IRP. It does not replace your GST number or your own invoice number; record all three against the same transaction.
E-invoicing concepts: authorised IRP FAQs. Invoice numbering: GST portal guidance.
02 / Check the requirement firstA GSTIN is the starting point.
A GSTIN is the starting point.
Not the eligibility decision.
Do not assume every GST-registered business must report every invoice. Confirm the current notified turnover criteria, covered documents and transactions, and applicable exemptions before setting up the workflow.
Check official e-invoice resourcesBusiness-level check
Ask your tax team to review the relevant turnover history and entity category. A single invoice value does not establish whether the supplier falls within the mandate.
Transaction-level check
Identify the document and recipient category. Do not treat a registered-business sale, an export and a consumer sale as interchangeable cases.
Reporting-time check
Plan reporting within the applicable time limit. Portal enablement is not a substitute for checking your legal obligations.
Timing advisory: from 1 April 2025, taxpayers with AATO of ₹10 crore and above face a 30-day reporting restriction for invoices, credit notes and debit notes. This is a reporting limit, not the general applicability threshold. Read the IRP advisory and check for updates.
03 / Follow the document
Five steps from preparation to reconciliation.
- 01
Prepare the invoice in your own system
Begin in your accounting or billing software. Assemble the document number, date, items, values and tax details. Keep an internal reference so your team can trace the same transaction from preparation to reconciliation.
- 02
Check the GST numbers and party details
Match the supplier registration and, for a registered buyer, the recipient GSTIN with the intended transaction. Review the billing and delivery details separately. A familiar company name is not a reason to skip checking the full GST number.
- 03
Report the structured invoice data
For a covered transaction, submit the prescribed data to an authorised Invoice Registration Portal (IRP). Use your supported software or the portal’s permitted workflow. Resolve validation errors before treating reporting as complete.
- 04
Receive the registration response
Successful reporting returns the Invoice Reference Number (IRN) and signed QR code with the signed invoice data. Keep the response associated with the original document; an upload attempt alone is not a successful registration.
- 05
Share, retain and reconcile
Provide the invoice with the required IRN and signed QR details, retain the supporting records and reconcile the transaction in your accounts. Separately review return data and any transport-document requirement before closing the task.
Process background: IRP FAQs. This is a practical preparation checklist, not an invoice submission facility.
04 / Read the result correctly
The reference and the verification aid.
IRN: keep the record connected
Store the portal reference alongside your invoice number. When a customer or colleague raises a query, start with that document pair instead of searching by company name alone.
- Keep the original reporting response.
- Match the reference to the right document.
- Review the current record if cancellation is involved.
Signed QR code: verify, then compare
Use an authorised verification tool for the signed QR code or signed invoice. Compare the returned details with the document in front of you; the presence of a square barcode alone is not sufficient.
- Use the tool intended for GST e-invoices.
- Compare party and document details.
- Investigate mismatches before relying on the invoice.
05 / Put the pieces together
A buyer receives an invoice. What should match?
Illustrative example · fictional businesses
Northstar Components bills Cedar Works.
The accounts team receives invoice NS/26/104. Before processing it, they compare the supplier identity, document details and applicable e-invoice record. A recognisable trading name is only the beginning of that review.
No real GSTIN, IRN or QR code is represented in this example.
- Registration
- Is the supplier GSTIN the registration intended for this purchase?
- Transaction
- Do invoice NS/26/104, its date, items and values match the purchase records?
- Reported document
- Where e-invoicing applies, do the verified signed details correspond to this invoice?
Clear up the common mix-ups
Questions before you report or accept an invoice.
Can I retrieve every e-invoice using a GST number?
Not through GSTVibe. Our registration lookup does not provide a business’s invoice history. Use the authorised portal facilities and appropriate access for invoice-specific records.
Is an emailed PDF automatically an e-invoice?
No. The file format and delivery method are separate from registration through the IRP. Review the applicable reporting requirement and the actual registration response.
Does an e-invoice replace an e-way bill?
No. Invoice reporting and goods-movement documentation serve different purposes. Where goods are moving, check the e-way bill requirement separately. Our e-way bill guide explains that journey.
Does generating an IRN file my GST return?
No. E-invoice information can be auto-populated into GSTR-1, but review, reconciliation and filing remain separate responsibilities. Check the GST portal’s GSTR-1 guidance before filing.
What should I do if reporting fails?
Read the actual validation message. Compare it with the source document, registration details and applicable reporting window. Keep the error reference and seek authorised support rather than repeatedly submitting guessed corrections.
Can GSTVibe generate or correct my e-invoice?
No. This page is educational. We do not collect portal passwords, submit invoice data, issue IRNs or amend records. Use your authorised reporting workflow for those actions.
Two checks. One clearer process.Know the registration.
Know the registration.
Then check the invoice.
Keep business verification, invoice reporting and return reconciliation connected—without treating them as the same task.
Reviewed 25 September 2026 using the linked GST and authorised IRP resources. General information only, not tax advice. Verify current notifications, exemptions and reporting advisories for your business.