Step-by-Step Process to Generate an e-Invoice and IRN

Updated on: Apr 11th, 2025

4 min read

‘How to generate e invoice’ has been one of the popular questions asked by many taxpayers. e-invoice is a B2B/B2G/export invoice reported by certain applicable GST-registered businesses with the e-invoice portal (GSTN), which must adhere to the standard format notified by the CBIC. This article will take you through the process of the generation of an IRN for e-invoice and also its workflow.

Latest Updates
4th April, 2025
With effect from June 1, 2025, IRP will treat invoice numbers as case-insensitive for IRN generation. All invoice numbers in any format will be converted to uppercase to avoid duplication and ensure consistency.
10th May 2023
CBIC notified the 6th phase of e-invoicing. Hence, taxpayers having more than Rs 5 crore turnover in any financial year from 2017-18 shall issue e-invoices w.e.f 1st August 2023.

06th May 2023
The GST department has deferred the time limit of 7 days to report the old e-invoices on the e-invoice IRP portals by three months. Also, the department is yet to announce the new implementation date.

13th April 2023
The GSTN released an advisory on 12th and 13th April 2023 stating that taxpayers with an annual turnover of Rs.100 crore and more must report tax invoices and credit-debit notes to the IRP within 7 days from the date of issue of the invoice/CDN from 1st May 2023.

30th January 2023
Few updates are made on the NIC's e-invoice portal-
(1) User can select POS state code of '96-Other Country' against items where HSN codes are 9965 and 9968 (Services by way of transportation of goods, including by mail or courier).
(2) The documents dated 1/10/2021 or after shall only be considered on the portal.
(3) The portal has added a new error code 2295 for duplicate requests apart from 2150, with error as 'IRN is already
generated and registered with GSTN Lookup Portal by other IRP'.

Steps to generate an e-invoice

Following is the e invoice procedure for applicable businesses who want to know how to generate e invoice –

Step 1 – Creation of the invoice on the taxpayer’s ERP

The taxpayer will continue to generate invoices in the normal course of business. However, the reporting of these invoices electronically has criteria. It needs to be done as per the e-invoice schema along with mandatory parameters. This is a one-time step for those who want to know how to generate e invoice. The mandatory fields of an invoice for the supply of goods are listed below:

Sl. no.	Name of the field	List of Choices/ Specifications/Sample Inputs	Remarks
1	Document Type Code	Enumerated List such as INV/CRN/DBN	Type of document must be specified
2	Supplier_Legal Name	String Max length: 100	Legal name of the supplier must be as per the PAN card
3	Supplier_GSTIN	Max length: 15 Must be alphanumeric	GSTIN of the supplier raising the e-invoice
4	Supplier_Address	Max length: 100	Building/Flat no., Road/Street, Locality, etc. of the supplier raising the e-invoice
5	Supplier_Place	Max length: 50	Supplier’s location such as city/town/village must be mentioned
6	Supplier_State_Code	Enumerated list of states	The state must be selected from the latest list given by GSTN
7	Supplier Pincode	Six digit code	The place (locality/district/state) of the supplier’s locality
8	Document Number	Max length: 16 Sample can be “ Sa/1/2019”	For unique identification of the invoice, a sequential number is required within the business context, time-frame, operating systems and records of the supplier. No identification scheme is to be used
9	Preceeding_Invoice_Reference and date	Max length:16 Sample input is “ Sa/1/2019” and “16/11/2020”	Detail of original invoice which is being amended by a subsequent document such as a debit and credit note. It is required to keep future expansion of e-versions of credit notes, debit notes and other documents required under GST
10	Document Date	String (DD/MM/YYYY) as per the technical field specification	The date when the invoice was issued. However, the format under explanatory notes refers to ‘YYYY-MM-DD’. Further clarity will be required. Document period start and end date must also be specified if selected.
11	Recipient_ Legal Name	Max length: 100	The name of the buyer as per the PAN
12	Recipient’s GSTIN	Max length: 15	The GSTIN of the buyer to be declared here
13	Recipient’s Address	Max length: 100	Building/Flat no., Road/Street, Locality, etc. of the supplier raising the e-invoice
14	Recipient’s State Code	Enumerated list	The place of supply state code to be selected here
15	Place_Of_Supply_State_ Code	Enumerated list of states	The state must be selected from the latest list given by GSTN
16	Pincode	Six digit code	The place (locality/district/state) of the buyer on whom the invoice is raised/ billed to must be declared here if any
17	Recipient Place	Max length: 100	Recipient’s location (City/Town/Village)
18	IRN- Invoice Reference Number	Max length: 64 Sample is ‘a5c12dca8 0e7433217…ba4013 750f2046f229’	At the time of registration request, this field is left empty by the supplier. Later on, a unique number will be generated by GSTN after uploading of the e-invoice on the GSTN portal. An acknowledgement will be sent back to the supplier after the successful acceptance of the e-invoice by the portal. IRN should then be displayed on e-invoice before use.
19	ShippingTo_GSTIN	Max length: 15	GSTIN of the buyer himself or the person to whom the particular item is being delivered to
20	Shipping To_State, Pincode and State code	Max length: 100 for state, 6 digit pincode and enumerated list for code	State pertaining to the place to which the goods and services invoiced were or are delivered
21	Dispatch From_ Name, Address, Place and Pincode	Max length: 100 each and 6 digit for pincode	Entity’s details (name, and city/town/village) from where goods are dispatched
22	Is_Service	String (Length: 1) by selecting Y/N	Whether or not supply of service must be mentioned
23	Supply Type Code	Enumerated list of codes Sample values can be either of B2B/B2C/ SEZWP/S EZWOP/E XP WP/EXP WOP/DE XP	Code will be used to identify type of supply such as business to business, business to consumer, supply to SEZ/Exports with or without payment, and deemed export.
24	Item Description	Max length: 300 The sample value is ‘Mobile’ The schema document refers to this as the ‘identification scheme identifier of the Item classification identifier’	Simply put, the relevant description generally used for the item in the trade. However, more clarity is needed on how it needs to be described for every two or more items belonging to the same HSN code
25	HSN Code	Max length: 8	The applicable HSN code for particular goods/service must be entered
26	Item_Price	Decimal (12,3) Sample value is ‘50’	The unit price, exclusive of GST, before subtracting item price discount, can not be negative
27	Assessable Value	Decimal (13,2) Sample value is ‘5000’	The price of an item, exclusive of GST, after subtracting item price discount. Hence, Gross price (-) Discount = Net price item, if any cash discount is provided at the time of sale
28	GST Rate	Decimal (3,2) Sample value is ‘5’	The GST rate represented as a percentage that is applicable to the item being invoiced
29	IGST Value, CGST Value and SGST Value Separately	Decimal (11,2) Sample value is ‘650.00’	For each individual item, IGST, CGST and SGST amounts have to be specified
30	Total Invoice Value	Decimal (11,2)	The total amount of the Invoice with GST. Must be rounded to a maximum of 2 decimals

The seller has to ensure that his accounting/billing software is capable of generating a JSON file of the final invoice. The seller can create a JSON file following the e-invoice schema and mandatory parameters by using the following modes:

An accounting and billing system that offers this service
A utility to interact with the accounting/billing system, or ERP, such as an excel/word document or a mobile app
An offline Tool to generate e-invoices by keying-in invoice data

Step 2 – Generation of the unique IRN

The next step in ‘how to make e invoice’ is reporting to the Invoice Registration Portal or IRP. The IRN (also known as hash) is a unique number which is generated by the e-invoice system using a hash generation algorithm. For every document submitted, a unique 64-character IRN will be generated. At present, the e-invoice system provides two modes to generate the IRN (Invoice Reference Number), i.e offline and API. Notified taxpayers who need to generate e-invoices, can generate them using these options:

Using the offline tool

If anyone is seeking the answer to how to generate e invoice manually, they can upload invoices in the standard format in a spreadsheet and the IRN can be generated in one go. Users can visit the e-invoice portal, and view the procedure for preparing a bulk upload request for IRNs at Help -> Tools -> Bulk Generation tools. Once the bulk upload request file has been prepared, the same needs to be uploaded in order to generate the IRNs. Once generated, the IRN form will all the details can be downloaded.

Using API (Through GSPs integration

Using API through GSP integration, system integration can be done with the help of registered GSPs (GST Suvidha Providers). Before using this mode, the API integration with the identified GSP will need to be tested in a sandbox environment. After the test, the GSP will need to submit the test summary report on the sandbox portal. The GSP will need to be registered on the e-invoice portal if not already registered.

If the same GSP is being used as on the e-way bill portal, there is no need to register again, and the same login credentials can be used. An API user will need to be created by entering a username and password. Using these credentials, a token and request for the IRN can be generated.

Using API (Through direct integration)

Using API through direct integration, the taxpayers’ systems can be directly integrated. The API integration will need to be tested in a sandbox environment. After the test, the taxpayer will need to submit the test summary report on the sandbox portal.

The taxpayer will need to get registered on the e-invoice portal if not already registered. If registered on the e-way bill portal, the same login credentials can be used. If the taxpayer is already integrated with API on the e-way bill system, the same API credentials can be used. If not, he will need to get API registration done using IP whitelisting.

If a sister concern having the same PAN has already registered for API and has had IP whitelisting done, the same client-ID credentials can be used. However, the new API user will need to be registered.

Using API (Through an enabled sister concern’s GSTIN)

Systems can be integrated using API, through the sister company of the taxpayer having the same PAN, if the same has been enabled for API. The API integration will need to be tested in a sandbox environment. After the test, the taxpayer will need to submit the test summary report on the sandbox portal. The IP used by the sister concern and the concerned taxpayer should be the same when accessing the e-way bill and e-invoice production APIs.

The taxpayer will need to get registered on the e-invoice portal if not already registered on the e-way bill portal. If registered on the e-way bill portal, the same login credentials can be used. If the taxpayer is already integrated with API on the e-way bill system, the same API credentials can be used. If not, he will need to create a new API user.

E-way Bill API-enabled Taxpayers

System integration using API can be done for e-way bill-enabled taxpayers. The taxpayer will need to test the API integration in a sandbox environment. After the test, the taxpayer will need to submit the test summary report on the sandbox portal. If the taxpayer is already API-enabled on the e-way bill system, the same credentials can be used. There is no need for any further steps.

Step 3 – Generation of the QR Code

The e-invoice system will generate the IRN, and then digitally sign the e-invoice and the QR code (quick response code). The QR code will enable a quick view, validation and access to the invoices from handheld devices. The QR code will consist of the following parameters:

The GSTIN of the supplier
The GSTIN of the recipient
The invoice number as given by the supplier
The date of generation of the invoice
The invoice value (taxable value and gross tax amount)
The number of line items
The HSN code of the main items (the line item having the highest taxable values)
The unique IRN (hash)

The digitally signed QR code will have a unique IRN (hash) which can be verified on the central portal, as well as by offline apps. This will be helpful for tax officers who need to check invoices in places where an internet connection may not be available, such as on highways.

Back-end processing of a valid e-invoice

The signed e-invoice data will be sent to the GST system where GSTR-1 of the supplier and GSTR-2B/2A of the buyer will be updated based on the details entered in the invoice. Wherever applicable, details of invoices will be used to update ‘Part A’ of the E-Way Bill. As a result, only the vehicle number needs to be entered in ‘Part B’ of the E-Way Bill system to create an E-Way bill.

Frequently Asked Questions

Can we generate e-invoice on portal?

You cannot raise or generate e invoice directly from GST Portal, since e invoicing is a process of only validating all the B2B invoices electronically by the GST Network (GSTN). Also, it is not convenient to generate e invoice, especially in bulk directly from the e invoice portal.

How do I get an e-invoice in the GST portal?

If you are a first-time user, then visit the e-invoice portal -> registration menu -> click on ‘e-Invoice Enablement’. Enter a particular GSTIN of the company and get the OTP verification done. Enter the annual turnover details with the related financial year and submit. You can get registered for e-invoicing. Next time onwards, login to the e-invoice portal and upload B2B invoices using a chosen mode to generate IRN.

What is the time limit for the generation of IRN?

There is no set time limit. You can generate e invoice within a few days after the date of the B2B invoice. However, it is recommended for you to generate IRN within the Time of Supply provisions of the CGST Act.

About the Author

AJ

Manager - Content

As a qualified Chartered Accountant with extensive expertise in accounting, finance, taxes, and audit, I specialise in simplifying complex regulations for a broader audience. Well-versed in tax laws across India and the GCC region, I have a keen interest in the evolving finance ecosystem. Passionate about learning, I enjoy engaging in conversations, exploring new cultures through travel, and unwinding with music.. Read more

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