ShipStation and Prophet 21: How the Integration Works

Many distributors on Epicor Prophet 21 (P21) use ShipStation to gather the orders from their web stores and marketplaces in one place. P21 still needs those orders: for inventory, pricing, invoicing and the general ledger.
This guide explains how Comparatio connects the two: what moves and in which direction, how each order is matched to your P21 records, and how setup, testing and support work. It describes the ShipStation connection as it runs in production on P21 today.
Why Connect ShipStation to Prophet 21?
Without a connection, someone retypes each web order into P21: the item, the quantity, the price and the ship-to. That takes time on every order, and retyping creates errors, such as the wrong item or a mistyped address.
With a connection, each order arrives in P21 as a sales order carrying the data the buyer entered. Anything that does not match your P21 records, such as an unknown SKU or a buyer with no ship-to, is flagged to your team instead of guessed.
Seamless EDI & ERP Integration
Connect your ERP, WMS, and business systems with automated EDI processing that eliminates manual data entry and reduces errors.
Schedule a Discussion
How Does the ShipStation and Prophet 21 Integration Work?
Which way does data move?
One way: from ShipStation into P21. Comparatio reads orders from ShipStation's API and creates them as P21 sales orders. It does not write orders, shipments or tracking numbers back to ShipStation.
What happens to each order?
- Pick-up. Comparatio checks ShipStation's API for new orders on a schedule, reading only the pages it needs. It looks back over recent days, so an order missed in one cycle is caught in the next.
- Log. Every order is logged in the EDI Portal with ShipStation's original order data, so you can see exactly what arrived.
- Duplicate check. The ShipStation order number is checked against the orders already imported. An order is entered once, however often it is read.
- Ship-to. The buyer's email is matched to a P21 ship-to under the customer set up for your ShipStation account, or the order uses a default ship-to you choose. The delivery name and address from ShipStation go on the order. If no ship-to fits, the order is held, and your team gets an email asking for the ship-to and contact so the order can be resent.
- Items. Each SKU is matched to a P21 item. A SKU that matches no item is flagged in the order email, or replaced by a substitute item you choose so the order still imports.
- Sales order. The order is created through the same P21 order import as your EDI purchase orders, with the same options: your contract pricing or the store's price, and the order taker and order class you choose.
- Confirmation. Your team gets an email for each imported order, listing its lines and flagging anything that needs a look.
How do ShipStation fields map to P21?
- Order number: the PO number on the P21 sales order, and the key for the duplicate check.
- ShipStation order ID: kept on the order as a reference.
- Order date: the order date.
- Ship-to name and address: the delivery address on the order.
- Customer email: used to find the P21 ship-to.
- SKU: the P21 item.
- Item name, quantity and unit price: the line description, quantity and price.
- Shipping amount: noted on the order, with a freight line for your freight handling.
How does Comparatio sign in to ShipStation?
With an API key and secret that you create in your ShipStation account, over an encrypted connection (TLS 1.2 or later). Comparatio only reads orders with them.
What Does Setup Look Like?
What do you need to provide?
- A ShipStation API key and secret.
- The P21 customer the orders belong under, and a default ship-to if your buyers are not set up as ship-tos.
- Your choices on pricing (contract pricing or the store's price), order taker and order class.
- A P21 test environment for the first orders.
- The email address that should receive order confirmations.
How is it tested?
The connection runs in test mode first, importing into your P21 test environment. You check the first orders in P21: customer, ship-to, items, prices and freight. Once they look right, we switch the connection to live.
Who does what?
| Task | Comparatio | Your team |
|---|---|---|
| ShipStation connection | Sets up and maintains the API connection | Creates the API key and secret in ShipStation |
| P21 setup | Configures the customer, default ship-to, pricing, taker and class | Decides them, and keeps items and ship-tos current in P21 |
| Testing | Runs the connection in test mode against your P21 test environment | Checks the test orders in P21 |
| Exceptions | Is alerted when an order fails to import, and follows up | Adds a missing ship-to or item flagged in an order email |
| Changes | Changes the setup when your stores, SKUs or rules change | Tells us what changed |
How Does ShipStation Fit With Your EDI?
The ShipStation connection runs inside Comparatio EDI, next to your EDI trading partners, as a Windows service or program on your server or one we host for you. It uses the same P21 connection and the same order import as your EDI orders, and the same engineers watch both.
That matters when you sell through more than one channel. Your EDI customers, such as the national distributors on our trading partner network, keep their acknowledgments, ship notices and invoices, while web-store orders come in through ShipStation. Marketplaces and web stores can also connect directly; our eCommerce integrations and Amazon EDI integration pages cover those.
If Epicor hosts your P21, the P21 connection is the one your EDI already uses. Our guide to EDI with Epicor-hosted P21 explains how that works. For everything else Comparatio does on P21, see Prophet 21 EDI integration.
Next Step
Want to see how your ShipStation orders would land in P21? Schedule a discussion and bring a sample order. We will walk through the customer, ship-to, items and pricing it would get.
Frequently Asked Questions
Does ShipStation integrate with Epicor Prophet 21?
Yes, through Comparatio. Comparatio reads orders from ShipStation's API and creates them as P21 sales orders, matching each order's ship-to and SKUs to your P21 records. The connection runs in production on P21 today.
Which way does data move between ShipStation and P21?
One way, from ShipStation into P21. Comparatio does not write orders, shipments or tracking numbers back to ShipStation.
What happens when a ShipStation SKU doesn't match a P21 item?
The order email to your team flags the SKU. If you choose a substitute item, the order still imports with that item, so nothing waits while the SKU is fixed.
What if the buyer isn't set up as a ship-to in P21?
The order can use a default ship-to you choose, with the delivery address from ShipStation on the order. If no ship-to fits, the order is held and your team is emailed to add the ship-to and contact.
Can the same ShipStation order be imported twice?
No. Each ShipStation order number is checked against the orders already imported, so an order that is read again is not entered again.
Can we test before orders reach live P21?
Yes. The connection runs in test mode first, importing into your P21 test environment, and is switched to live once you have checked the first orders.
Table of Contents
Subscribe to the Blog
Get the latest EDI insights delivered to your inbox.
Related Articles

October 29, 2026
ERP EDI Integration for Manufacturers: A 5-Step Build Guide
A 5-step erp edi integration guide for manufacturers: map 850, 856 and 862 records, pick a method, handle errors, test with partners and decide build vs buy.
Read More →
October 29, 2026
NetSuite EDI With Suppliers: POs, ASNs and Vendor Bills
Supplier EDI in NetSuite: 850 POs out, 855s onto the Purchase Order, 856s as Inbound Shipments, 810s as Vendor Bills, and what your admin needs to set up.
Read More →
October 29, 2026
Prophet 21 Is Moving to Epicor's Cloud: What Changes for EDI
Epicor's last on-premises Prophet 21 release is 2028.1. What changes for EDI on Epicor-hosted P21: database access, SFTP imports, the P21 API and a plan.
Read More →Tell us who your trading partners are
Send us your partner list, and we’ll tell you which maps already exist and what a go-live plan looks like.