Everything About Invoice Reference Number (IRN)

What is IRN in GST?

IRN full form is Invoice Reference Number is a unique code generated by IRP (Invoice Registration Portal). Invoice reference number in GST is also known as hash as IRN uses a hash generation algorithm. IRN Number shall be generated for every invoice, debit, or credit note.

Why IRN is also known as Hash?

IRN e-invoice is also known as Hash as it uses a hash generation algorithm. This algorithm converts the message containing Alphanumeric codes and certain special characters into unique numbers in such a way that the original message cannot be decoded easily in IRN in GST. The generation of this algorithm will mainly depend upon the GSTIN under the e-Invoicing system and even during IRN number tracking.

Decoding Invoice Reference Number (IRN) or Hash

As we already know IRN number full form; the IRN or Hash is a unique number generated by changing characters into numbers through hash generation algorithms. The three important part on which IRN generation and IRN Number Digits will depend is the below given IRN number example -

1. The GSTIN of the Supplier
2. Invoice number of the supplier
3. The format of the financial year (FY), i.e. ‘YYYY-YY’. For instance 2020-21.

Pre-requisite to Generate IRN

Here are some of the prerequisites at the time of how to generate IRN number and IRN number search:

1. The Document Date should be less than or equal to the current date.
2. The following types of documents are only considered for the generation of IRN.
   • Invoice
   • Debit Note
   • Credit Note.
3. E-Invoice requests should be made only for the following category of transactions
   • Business to Business(B2B) invoices
   • Business to Government (B2G) invoices
   • Business to Export invoices
   • Reverse Charges invoices
   • Supplies through e-Commerce Operator
4. A supplier should ensure that the unique invoice number is being generated for the financial year for each invoice, in his ERP/manual system. For the financial year, the date of the invoice is considered. The financial year starts on 1st April and ends on 31st March.
5. Requests for the IRN/e-Invoice can be made only by the supplier of the goods or services. However, the e-Commerce Operator can request the IRN/e-invoice on behalf of the supplier. In this case, the e-Commerce Operator should have registered on the GST portal accordingly.
6. The IRN can be generated and passed by the taxpayer’s system on the combination of Supplier GSTIN, Financial Year, document type and document number.
7. e-invoice(IRN) can be re-generated for the cancelled e-invoice(IRN)
8. Duplicate IRN requests are not considered, i.e., if the IRN is already generated on a particular type of document and the document number of the supplier for the financial year, then one more IRN cannot be generated on the same combination.
9. In the case of export transactions, the taxpayer has to pass the following data
   • • The subtype of export
     • Payment type – With or Without
     • Port code
     • Country code
     • Currency and value

10. In the case of the Debit/Credit Note of the transaction, the taxpayer has to pass the Original Invoice Number in the Debit/Credit Note details.
11. PIN Codes are validated against the States, they belong to.
12. To identify the type of movement of goods, the type of transaction is being captured.
13. The recipient's GSTIN should be registered as an active GSTIN number. In case of a transaction of direct export, the recipient GSTIN has to be URP.
14. In the case of a ‘Bill to – Ship to’ transaction, the details of the recipient party(Bill-to) and shipping party (Ship-to) should be passed.
15. In the case of the ‘Bill From – Dispatch From’ transaction, the details of the supplier party(Bill-from) and dispatching party (dispatch-from) should be passed.
16. In the case of an intrastate transaction, where both Supplier GSTIN and recipient GSTIN belong to the same state, the SGST and CGST tax rates and values have to be passed.
17. In the case of an inter-state transaction, where both Supplier GSTIN and recipient GSTIN belong to different states, the IGST tax rate and value have to be passed.
18. In the case of the export transaction, the IGST tax rate and value have to be passed.
19. In case the supplier is SEZ unit, then the IGST tax rate and value have to be passed irrespective of the state of the buyer.
20. Each item needs to valid HSN code with at least 4 digits. That is, items of goods type should be 4 or 6 or 8 digits and items of service type should be 4 or 5 or 6 digits.
21. Tax rates are being validated. Only the allowed tax rates will be accepted.
22. The maximum number of items in each invoice should not exceed more than 1000 items.

The above-mentioned process is all about how to generate and how to verify IRN number, what is IRN code and even IRN full form in GST.