My Account

New: MCS webhooks for order and return updates

Date: September 28, 2026

Walmart Multichannel Solutions (MCS) now supports webhooks for real-time order, shipment, and return updates. Instead of repeatedly polling APIs for status changes, you can subscribe to supported events and receive notifications when key fulfillment and return activities occur. For more details, refer to the Walmart Multichannel Solutions (MCS) Webhooks Guide.

What’s changed

Added support for these MCS webhook event types:

  • Order status updates: Receive ORDER_STATUS_UPDATE notifications when an order is acknowledged, shipped, or canceled.
  • Shipment updates: Receive ORDER_SHIPMENT_UPDATE notifications when shipment information changes, including tracking numbers, carrier information, and shipment status.
  • Return updates: Subscribe to MCS_RETURN_ORDER_STATUS_UPDATE to receive notifications throughout the return lifecycle. The specific return event is identified by the payload.header.eventName field.

Return notifications include events authorization, label generation, cancellation, in-transit updates, delivery to the return center, receipt and disposition, and disputes.

Why it matters

  • Reduce repeated API polling for order, shipment, and return status changes.
  • Keep order and return information synchronized across your systems.
  • Monitor fulfillment and return activity as changes occur.
  • Automate downstream workflows based on order, shipment, return, and disposition events.
  • Capture relevant carrier, tracking, disposition, and dispute information from webhook notifications.

Next steps

  • Review the supported MCS webhook events and determine which notifications your integration needs.
  • Use the Get webhook event types API to retrieve event types available for subscription.
  • Use the Create webhook subscription API to subscribe to the required events and provide a publicly accessible HTTPS endpoint.
  • Update your integration to process webhook payloads and use eventId to identify and handle duplicate events.
  • Refer to the Walmart Multichannel Solutions (MCS) Webhooks Guide for payload examples, field descriptions, return event details, and implementation guidance.