Guides
  1. E-Invoice

Cancel an IRN

NIC permits IRN cancellation within 24 hours of generation. Past the window, the IRN cannot be cancelled — you'd issue a credit note (documentType: "CRN") referencing the original invoice instead.

The call

POST /v1/einvoices/cancel HTTP/1.1
Host: api.in.onefinops.com
Authorization: Bearer eyJhbGciOi...
gstin: 36AMBPG7773M002
Content-Type: application/json
X-Request-Id: 4f1d8a2c-…

Body:

{
  "irn": "a1b2c3d4e5f6...",
  "reasonCode": "1",
  "remarks": "Duplicate IRN — invoice was registered twice."
}

reasonCode is NIC's cancellation reason:

ValueReason
"1"Duplicate
"2"Data entry error
"3"Order cancelled
"4"Other

remarks is required (max 100 characters, free text). NIC stores it verbatim against the cancellation record.

Successful response

{
  "irn": "a1b2c3d4e5f6...",
  "ackNumber": 112324567890123,
  "ackDate": "2026-05-14T11:42:18.000Z",
  "status": "CNL",
  "cancelDate": "2026-05-14T13:22:18.000Z",
  "remarks": "Duplicate IRN — invoice was registered twice."
}

After cancellation:

  • Status moves to CNL. Cancelled records are never deleted by NIC — they remain part of the audit trail and are still fetchable via GET /v1/einvoices/irn?irn=….
  • The signed JWS and QR are no longer returned on re-fetch. They were valid at the moment of registration; once cancelled, presenting them as a current invoice would be misleading.

If a linked EWB exists

NIC refuses to cancel an IRN while an active EWB is linked to it. Cancel the EWB first (POST /v1/ewaybills/cancel), then retry the IRN cancellation. The error you'd see otherwise:

{
  "code": "upstream.failure",
  "message": "EWB is active — cancel the EWB first",
  "upstream": { "code": "4002", "message": "EWB is generated for this IRN" }
}

Failure paths

StatusBody codeMeaning
404not_foundThe IRN doesn't belong to your tenant.
409einvoice.cancel_window_expiredMore than 24 hours since ackDate. Issue a credit note instead.
409einvoice.not_cancellableIRN isn't in a cancellable state (already cancelled, or it failed to register in the first place).
422validation_errorreasonCode or remarks failed validation.
502upstream.failureNIC refused — read upstream.code and upstream.message. The linked-EWB case above is the most common.

Coordinating with downstream systems

Cancellation is permanent. If you have downstream systems consuming the IRN (analytics, GSTR-1 filings, customer portals), keep them in sync by re-fetching the IRN with GET /v1/einvoices/irn?irn=… after cancellation so they don't keep acting on a stale ACT snapshot.

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