
e-Invoicing under GST: Everything you need to know about the e-Way Bill APIs
Introduction
The implementation of e-Invoices has changed the various aspects of GST significantly.
It is not a surprise that e-Invoicing under GST has affected GST Compliance to a large extent, starting from GST Filing, to Reconciliation, ITC, Refunds & e-Way Bills.
However to connect all these aspects of GST electronically, a strong API framework is necessary & the government has taken the same into consideration.
As they released the e-Invoicing & e-Way bill APIs to ease the e-Way Bill compliance through IRNs & IRP.
In this blog we have explained the details of these APIs & their functions so you can understand how they work towards making GST compliance simple for you.
e-Invoices & e-Way Bills under GST

e-Way Bills are relatively known to businesses by now considering that they were introduced a long while ago. But also because the government rolled out many strict rules to make businesses comply with the provisions of the e-Way Bills.
So e-Way Bills are documents that the transporter of the goods need to carry when the consignment is in transit.
This contains some of the invoice & item details & is a mandatory document with time validity.
e-Way Bills are generally generated on the e-Way Bill portal and accounted in the billing systems for the record.
On the other hand, e-Invoices are newly introduced upgraded version of the traditional paper invoices.
However, the drill is that these invoices are completely electronic, meaning there is a standard for at specified by the government in which these invoices are to be made by businesses & accountants.
Later you need to declare these invoices on the IRP for validation purposes. The portal will validate your invoices & assign a unique QR code & hash generated IRN.
Only then will the e-Invoices be called valid & will be considered as suitable to use for carrying out business.
Read Also: e-Invoicing under GST- Applicability & Exemption!
Like e-Way Bills e-Invoices are also mandatory for select class of business, transactions & documents.
There is a major link between the two documents; either of the two tends to support each other.
For example, for any missing e-Way Bills, a valid e-Invoice can back up that transaction, and vice versa.
e-Way Bills are mostly generated against Invoices, Credit & debit notes, all these documents are liable to invoicing.
API Specifications to Link e-Way Bills with e-Invoices
The government has additionally launched API specifications to merge e-Way Bills with e-Invoices even further.
There are two new APIs that the government has lunched-
- Generate IRN
- Generate EWB by IRN
Now what does this mean?
It means that you can generate e-Way Bills from the Invoice Registration Portal in real time with the e-Invoice, using the two APIs.
To generate e-Way Bills along with e-Invoice- Generate IRN
This API will enable you to generate the e-Way Bills along with the e-Invoicing software. How? The Government has inserted new columns in the SCHEMA Format of the e-Invoice.
This new format contains a section for the e-Way Bill details as well. In this, if you furnish all the e-Way Bill details for generate both Part A & Part B, then the IRP will generate an e-Way Bill with validity, which you can put to use immediately.
If you only furnish the details of the e-Way Bill to generate Part-A, then Part of the e-Way Bill will be generated. You can later visit the e-Way Bill Portal & furnish the transporter details to generate Part B & activate the e-Way Bill.
The above two process happen at the time of e-Invoice & IRN generation itself.
Note- you can use the same API when you do not wish to generate an e-Way Bill along with the e-Invoice.
To Generate e-Way Bills after the IRN Generation- Generate e-way Bill by IRN

You can use this API if you are generating the e-Way Bill using the IRN, after the e-Invoice has been generated.
You can generate an e-Way Bill from the IRP itself using the IRN, all you need to do is provide the IRN & the e-Way Bill details.
Now depending on the type of detail that you provide the IRP will generate the Parts of the e-Way Bill accordingly.
If you provide complete transporter details then the IRP will generate an active e-Way Bill with validity.
And in case you provide minimum or half transporter details then only part A will be generated & you will have to update the Part B from the NIC e-Way Bill Portal.
Additional Validation Rules to note
- IRN cannot be cancelled if there is an active e-Way Bill against it.
- IRN & e-Way Bills cannot be cancelled post 24 hours of generation
- For cancelling them post the window you can generate credit Notes against them
- IRNs are to be generated in real time only, that is you cannot create back-dated e-Invoice
- IRN cannot be re generated for the cancelled e-Invoice. A new document with a new doc no. must be created to generate the IRN
- All the e-Way Bill Actions such as edit, validity extension etc. need to be done from the e-Way Bill Portal only.
- A cancelled e-Way Bill can be regenerated for the same documents using the NIC.
Conclusion
e-Invoicing compliance is of high priority for all businesses that are liable to it irrespective of its impact as it is a mandatory rule under the CGST Act 2017.
Compliance with this single provision, will help businesses comply with GST as a whole, considering that e-Invoices do reduce the compliance load.
So complying well with e-Invoicing alone will help business with the entire GST Compliance.
However, the compliance can sometimes be a little more difficult than it seems considering the complex SCHEMA Format, Real-time Validations, Bulk operations, Archiving and more.
The Government also recommends the use of external solutions such as GSPs to comply better with e-Invoicing, one such GSP is GSTHero which is also the best e-Invoicing Solution in the market currently.
GSTHero makes e-Invoicing simple to understand and operate with its user-friendly features and prominent support.
So why GSTHero?
- Simple ERP integration
- High Data Security
- Storage- e-Invoice Archiving for 8 years!
- Direct integration of ERP with the IRP
- Scalable for high data volume
- Super Automated- requires minimal human input
- Reduced Errors with automation
- Saves time and delivers prompt results
- Enhanced productivity of your accounts team
- Compliance in real-time
- Bulk Operations- Generate, cancel, print, validate and edit e-Invoice in bulk within the ERP
- Achieve 100% Compliance with e-Invoicing Cost-effective