Obtain your Narvar Account ID and Auth token from Admin > Company > API credentials in the Narvar portal; Narvar uses HTTP Basic authentication with the Account ID as the username and Auth token as the password.
Push order data to Narvar via the Order API, which requires order, order_items, shipment, billing, customer, and promotions fields; this baseline data is needed before returns can be initiated.
When a customer initiates a return through the Narvar Returns portal, Narvar creates a return record and triggers a return event that your integration can receive via the configured webhook endpoint.
Configure the webhook destination URL in the Narvar admin; Narvar posts JSON payloads containing the return ID, order reference, line items, return reason codes, and requested resolution (refund, exchange).
Update your OMS with the return details on webhook receipt; generate a prepaid return label via your carrier API and pass the tracking number back to Narvar so the portal shows return shipment status.
Poll or receive webhook events for return shipment status updates (in-transit, delivered to warehouse) to trigger inspection workflows and process refunds or exchanges in your system.
Known gotchas
Narvar's OAuth V2/V3 token-based access (Client ID and Client Secret) is required for newer Ship API endpoints; confirm which authentication version your Narvar account tier supports before building.
Order data must be sent to Narvar before a return can be started — missing or malformed order records (especially shipment tracking numbers) break the consumer-facing returns portal experience.
Narvar does not process refunds itself; it captures the return intent and ships the item back — your OMS or payment system must handle the actual refund upon confirmed receipt.
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