Missing Shipment ID in Fulfillment API Response

[aditya-rola]

I’m currently integrating ShipStation’s API into our ERP system and have run into an issue while working with the Fulfillments API.

To create a fulfillment, I understand that I need three main parameters:

• trackingNumber
• carrierCode
• shipmentId

I already have the tracking number and carrier, but I’m unable to find the shipment ID.

According to the ShipStation API documentation:

• The shipmentId should be available in the Order API response. However, I don’t see it there — I’ve checked the order details endpoint (`/orders/{orderId}`) and also /orders?orderNumber=XXXX.
• Another section mentions that I can retrieve it using the Fulfillment endpoint (/fulfillments?orderNumber=XXX). But when I call that endpoint, I get a 200 response with an empty list in the data.

I’ve double-checked the order number and even tried multiple test cases, but still no luck.

Has anyone faced this issue before or can confirm the correct way to obtain the shipmentId for a given order?
Is there any specific condition (like order status or fulfillment state) required before the shipment ID becomes available?

Any guidance or clarification from ShipStation Support or other developers would be greatly appreciated!

Thanks in advance!

[CaraAdmin]

Hello @aditya-rola!

First, welcome to the Community! We're so glad you're here. This space is a great place to find answers, share feedback, and suggest new product features—we hope you find it both helpful and inspiring!

I checked in with our support team, and they recommended this Help Center article on using the API for listing shipments. If you encounter any other issues with your API, please don’t hesitate to reach out to apisupport@shipstation.com—they’ll be happy to assist you further.

I hope you find this helpful! 

-Cara