> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fincelo.app/llms.txt
> Use this file to discover all available pages before exploring further.

# GST E-Invoicing

> IRN generation, QR code embedding, and GSTR-1 auto-population for India GST compliance.

## Overview

Fincelo handles the complete GST e-invoicing flow — from eligibility check to IRN generation to QR embedding to GSTR-1 auto-population. Zero manual steps required.

***

## E-Invoicing Flow

```
Invoice generated by Smart Billing Agent
        ↓
Eligibility check (turnover threshold)
        ↓
JSON payload built per IRP schema
        ↓
Sent to IRP (Invoice Registration Portal)
        ↓
IRN generated (64-char SHA-256 hash)
        ↓
QR code generated and embedded in PDF
        ↓
GSTR-1 auto-populated
```

***

## IRN Generation

Every B2B invoice above the e-invoicing threshold gets:

* **IRN** — 64-character SHA-256 hash, unique per invoice
* **Acknowledgement Number** — IRP reference
* **Acknowledgement Date** — timestamp of IRP registration

These appear on every invoice PDF automatically.

***

## Cancellation Rules

| Scenario                          | Action                                         |
| --------------------------------- | ---------------------------------------------- |
| Within 24 hours of IRN generation | Cancel IRN directly on IRP                     |
| After 24 hours                    | Cannot cancel — raise credit note with own IRN |

<Warning>
  Fincelo enforces the 24-hour cancellation window strictly. After 24h, the system blocks IRN cancellation and guides you to raise a credit note instead.
</Warning>

***

## Proforma Invoices

Proforma invoices (raised when PO not yet received) do **not** get an IRN:

* No invoice number
* No invoice date
* No GST
* No IRN

When PO is received, the proforma converts to a Tax Invoice with:

* Sequential invoice number (from that month's series)
* Invoice date = PO receipt date
* Full GST applied
* IRN generated

***

## GSTR-1 Auto-Population

Every IRN-registered invoice is automatically:

1. Added to the GSTR-1 data set
2. Categorised by invoice type (B2B, B2C, export)
3. Available for review before filing
4. Exported in the required JSON format for GST portal upload

***

## Setup Requirements

1. Your GSTIN configured in **Settings → Compliance**
2. Cleartax GSP API credentials (recommended) or direct IRP access
3. Digital signature certificate (for GST Rule 46 compliance)