Business · Live
E-Invoice API (IRN Generation)
Register an invoice and get its IRN, signed QR and acknowledgement.
What the E-Invoice (IRN) API does
Register invoices with the Invoice Registration Portal and receive the IRN, signed QR code and acknowledgement number in one call — the step that makes a B2B invoice legally valid above the e-invoicing threshold. Calls carry your own GST portal API credentials (GSTIN, username and password), so filings are made as you, on your own registration. We never file on our own account.
Popular use cases
- →Accounting and billing software registering invoices at issue
- →ERP systems automating B2B compliance above the turnover threshold
- →Marketplaces issuing invoices on behalf of registered sellers
curl -X POST https://apisathi.in/gw/v1/einvoice-generate-irn-v1/ \
-H "X-API-Key: live_xxx" \
-H "Content-Type: application/json" \
-d '{ "gstin": "23BEFPJ5660F2ZP", "username": "your_portal_user", "password": "•••", "payload": { "Version": "1.1", "DocDtls": { "No": "INV-001" } } }'{
"success": true,
"data": { "Irn": "a5c…", "AckNo": 112010036356, "SignedQRCode": "eyJ…" }
}Response fields returned by the E-Invoice (IRN) API
| Field | Example |
|---|---|
| success | true |
| data.Irn | a5c… |
| data.AckNo | 112010036356 |
| data.SignedQRCode | eyJ… |
Every field, error code and the full schema are in the E-Invoice (IRN) API reference.
Call the E-Invoice (IRN) API from Node.js or Python
const res = await fetch('https://apisathi.in/gw/v1/einvoice-generate-irn-v1/', {
method: 'POST',
headers: { 'X-API-Key': process.env.APISATHI_KEY, 'Content-Type': 'application/json' },
body: JSON.stringify({"gstin":"23BEFPJ5660F2ZP","username":"your_portal_user","password":"•••","payload":{"Version":"1.1","DocDtls":{"No":"INV-001"}}}),
});
const data = await res.json();import os, requests
res = requests.post(
"https://apisathi.in/gw/v1/einvoice-generate-irn-v1/",
headers={"X-API-Key": os.environ["APISATHI_KEY"]},
json={"gstin":"23BEFPJ5660F2ZP","username":"your_portal_user","password":"•••","payload":{"Version":"1.1","DocDtls":{"No":"INV-001"}}},
timeout=30,
)
data = res.json()E-Invoice (IRN) API pricing
- → From ₹3 per successful call + 18% GST
- → Prepaid wallet from ₹200; no monthly fee, no minimum volume
- → Failed or timed-out calls are not charged
- → Bonus credit on recharges of ₹1,000 and above; GST invoice on every recharge
Start in four steps
- Create a free account — about a minute.
- Call the E-Invoice (IRN) API with your TEST key in the sandbox, free.
- Recharge the wallet (UPI, card or netbanking) from ₹200.
- Switch to your LIVE key — the same key works for every API.
Frequently asked questions
What is an IRN and when do I need one?
The Invoice Reference Number is issued by the government when an invoice is registered. Businesses above the e-invoicing turnover threshold must register B2B invoices before issuing them.
Do you store my invoice data?
No. The payload is relayed to the portal and the response returned to you. We record the call for billing and support — never the invoice contents.
Can I generate an e-way bill from the IRN?
Yes, without re-keying the invoice. There is a separate endpoint that raises the e-way bill directly from a registered IRN.
How much does the E-Invoice (IRN) API cost?
The E-Invoice (IRN) API on API Sathi starts at ₹3 per successful call plus 18% GST, paid from a prepaid wallet. There is no monthly fee or minimum volume, and recharges of ₹1,000 or more earn bonus credit. Live prices for every API are on the pricing page.
Can I test the E-Invoice (IRN) API for free?
Yes. Every account gets a TEST key that calls the E-Invoice (IRN) API in the sandbox at no cost and returns realistic sample responses, so you can finish your integration before adding money to the wallet.
Am I charged if a E-Invoice (IRN) API call fails?
No. You pay only for successful calls. If the source is unavailable, times out or rejects the request, the amount held for that call is released straight back to your wallet.
How do I get a E-Invoice (IRN) API key?
Sign up at apisathi.in — it takes about a minute — and create a key under API Keys. Use the TEST key in the sandbox, then recharge from ₹200 and switch to a LIVE key. The same key works for every API on API Sathi.
Related APIs
Udyam Verification API
Confirm MSME status and pull the full Udyam record.
From ₹15/call
GST Verification API
Validate any GSTIN and fetch taxpayer details in one API call.
From ₹1.20/call
Company / CIN Verification API
Resolve companies, CINs, PANs and directors from the MCA graph.
From ₹3.60/call
E-Way Bill API
Generate an e-way bill for any consignment in a single API call.
From ₹3/call
E-Invoice Cancellation API
Cancel a registered IRN within the window the portal allows.
From ₹3/call
E-Way Bill Cancellation API
Cancel an e-way bill you generated, in one call.
From ₹3/call
Start using the E-Invoice (IRN) API today
Sign up, recharge a prepaid wallet and generate a key in minutes. Lowest price guaranteed, no volume commitment.