When people hear e-invoicing, they often think it means generating invoices directly on the GST portal. That’s not true—and this misunderstanding alone causes a lot of confusion.
E-invoicing under GST is simply a system where your invoice is validated by the government before it is considered legally valid. It adds transparency, reduces fake invoices, and makes return filing smoother.
In this blog, we’ll explain e-invoicing in a very practical way—what it actually is, who must follow it, how it works, and what mistakes you should avoid.
What Is E-Invoicing Under GST?
E-invoicing means electronically reporting invoice details to the government’s Invoice Registration Portal (IRP) and getting a unique reference number.
Important point:
“You still create the invoice in your own billing software.”
The IRP:
- Validates invoice data
- Generates IRN (Invoice Reference Number)
- Adds a QR code
- Digitally signs the invoice
Without IRN, the invoice is invalid for GST purposes.
Who Is Required to Follow E-Invoicing?
E-invoicing is mandatory if:
- Aggregate turnover exceeds ₹5 crore
- Turnover is calculated from 2017–18 onwards
- Supply is B2B, export, or deemed export
It does not apply to:
- B2C invoices
- Composition taxpayers
- Non-GST supplies
Types of Documents Covered Under E-Invoicing
E-invoicing applies to:
- Tax invoices
- Credit notes
- Debit notes
This directly connects with invoice structure explained earlier.
How the E-Invoicing Process Works (Step-by-Step)
Here’s the real flow, without jargon:
Step 1: Create Invoice
Create invoice in your accounting software (Tally, Zoho, ERP, etc.)
Step 2: Upload to IRP
Invoice data is uploaded to the Invoice Registration Portal
Step 3: IRP Validates Invoice
IRP checks:
- GSTIN
- Invoice number
- HSN/SAC
- Tax values
Step 4: IRN & QR Code Generated
If valid:
- IRN generated
- QR code added
- Invoice digitally signed
Step 5: Auto-Sharing With GST System
Invoice data flows automatically to:
- GST portal (GSTR-1)
- E-way bill system (where applicable)
What Is IRN (Invoice Reference Number)?
IRN is:
- A unique 64-character number
- Generated using supplier GSTIN + invoice number + financial year
It ensures:
- No duplicate invoices
- No fake invoices
Without IRN, invoice has no legal value.
QR Code on E-Invoice – Why It Matters
QR code contains:
- GSTIN of supplier & recipient
- Invoice number
- Invoice date
- Tax amount
- IRN
It allows:
- Instant verification
- Quick checks during audits
How E-Invoicing Helps Businesses
Though it feels strict, e-invoicing actually helps:
- Reduces data entry in returns
- Minimises invoice mismatches
- Faster e-way bill generation
- Less scope for GST notices
- Cleaner ITC flow
It connects well with mandatory invoice fields (Rule 46).
Common Mistakes in E-Invoicing
- Issuing invoice before IRN generation
- Cancelling invoice after 24 hours
- Wrong HSN or SAC
- Duplicate invoice numbers
- Uploading B2C invoices unnecessarily
Most rejections happen due to basic invoice errors.
Cancellation of E-Invoices
- Can be cancelled within 24 hours on IRP
- Cannot be partially cancelled
- After 24 hours → cancel through GST returns
Once again, invoice accuracy matters.
How E-Invoicing Connects With Other GST Rules
E-invoicing depends heavily on:
- HSN code accuracy
- Mandatory invoice fields
- Correct tax invoice timing
A small mistake in any of these breaks the chain.
Recommended Reading
For complete clarity, you should also read:
- Start with the basics in Understanding GST Tax Invoices: A Simple Beginner Guide to know how invoices drive GST.
- For invoice timing rules, refer to GST Tax Invoice Rules for Goods: Time, Format & Cases and GST Tax Invoice Rules for Services: Time, Limits & Use.
- If your business runs on contracts or subscriptions, Continuous Supply Under GST: Goods vs Services Explained explains recurring invoicing.
- To avoid rejection due to missing details, read Mandatory Fields of GST Tax Invoice: Rule 46 Explained.
- For classification accuracy, HSN Code Rules Under GST: Meaning, Limits & Errors is essential before e-invoicing.
These articles together form a complete GST invoicing framework.
FAQs
1. Is e-invoicing compulsory for all businesses?
No. Only if turnover exceeds ₹5 crore and for B2B/export supplies.
2. Can I generate e-invoice on GST portal?
No. Invoice is created in your own software and only validated on IRP.
3. Is e-invoice required for B2C invoices?
No. But QR code rules may apply separately.
4. Can an e-invoice be edited later?
No. You must cancel and reissue within allowed time.
5. Does e-invoice auto-populate GST returns?
Yes. Data flows to GSTR-1 automatically.
6. What happens if IRN is not generated?
Invoice is treated as invalid under GST law.
