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Amazon Warehouses & Prep Centers

Send purchase orders to prep with a review of every line

Connect a prep center, send purchase orders from Seller Assistant, and see what arrived.

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HOW IT WORKS

From warehouse setup to prep dispatch in 3 steps

No portal switching. The entire prep workflow happens where the order was created.

Add or sync your warehouses
WHY IT MATTERS

Managing prep was always the part that broke the workflow

Most sellers still re-enter every SKU in the prep center portal. Send to prep keeps that review in Seller Assistant.

Direct prep dispatch from purchase order
Direct prep dispatch

No more copying PO data into a separate portal

Send a purchase order to prep from Seller Assistant, and review every line before it goes.

Prep center directory

Purpose-built prep center integrations

Choose from a growing directory of prep centers with purpose-built integrations. No automation tools, no custom workarounds — connect directly from Seller Assistant. Don't see your prep center? Request it and we'll add it.

Prep center directory
Warehouse database with all locations
Warehouse database

One source of truth for all your locations

When you're running dozens of POs across multiple suppliers and prep centers, manual routing breaks down. All warehouses and prep centers in one shared database — assign once per supplier and every PO routes correctly, automatically, regardless of volume.

What's included

Everything warehouses database handles

From manual entry to a reviewed send, shared SKUs, and receipt sync.

Manual warehouse entry

Add any warehouse or prep center with name, address, and contact details

Prep center sync

Integrated warehouses sync automatically into your database

Supplier association

Link a warehouse to a supplier so the correct ship-to is applied automatically on every PO

Select ship-to from PO

Change the assigned warehouse directly from the PO header

Send to prep

Review each line, match the prep item, and send the order.

Receipt sync

See received, damaged, and missing units back on the purchase order.

Shipment unlinking

Unlink a shipment and send the order to another prep center.

Team access

Warehouses are shared across the team with full edit and delete permissions

WORKFLOW

Warehouses database connects the order to the prep center. These tools close the loop

The purchase order, the prep center, and the Amazon listing stay on the same SKU.

Source
Purchase Orders

Review every line in Send to prep, move the PO to Ordered, and resolve receiving gaps from the order

 Source
Suppliers

Link a warehouse to a supplier so the ship-to address is set automatically on every purchase order

 Source
FBA Shipments

Track inbound shipments after your prep center dispatches inventory to Amazon

 List
Lister

List new SKUs from the PO, with the marketplace and listing defaults already set
COMPLETE YOUR WORKFLOW

The pipeline starts long before the warehouse

Build your order list before anything reaches a purchase order.

Price List Analyzer

Turn a supplier catalog into a shortlist of profitable products ready to order.

Analyze
Products Database

Source products into your pipeline and push them into purchase orders.

Source
SKUs

Track landed costs per SKU with prep and inbound fees factored in automatically.

List
Brand Analyzer

Research brand performance before committing to a supplier.

Analyze
From the blog

How-tos and guides

How Prep Center Integration Works in Seller Assistant

How Prep Center Integration Works in Seller Assistant: Connect prep centers, sync warehouses, send Purchase Orders, and streamline Amazon fulfillment.

Seller Assistant Prep Center Integration: Full Guide

Seller Assistant Prep Center Integration: Learn how to connect prep centers, sync warehouses, streamline purchase orders, and simplify Amazon fulfillment

How to Use Seller Assistant’s Warehouses Database

Learn how to manage warehouses, prep centers, and fulfillment locations in one place with built-in Prep Center Integration.

Seller Assistant Warehouses Database: Full Guide

Seller Assistant Warehouses Database: Learn how to manage warehouses, prep centers, and fulfillment locations to streamline your Amazon sourcing workflow.

Suppliers and Warehouses: Connecting Your Workflow

Suppliers and Warehouses: Learn how to connect supplier profiles with warehouses in Seller Assistant to streamline purchasing and improve fulfillment routing.

Frequently Asked Questions

Visit Help Center
How do I send a purchase order to a prep center?
Open the PO assigned to a synced warehouse and click Send to prep. Seller Assistant reviews every line against the prep center, matches each one by a saved match, SKU, UPC or EAN, or ASIN and condition, or creates the item on send. You choose only when more than one item fits. A successful send moves the PO from Draft to Ordered and links the shipment back to the PO. This applies to prep centers connected through PrepBusiness-based integrations.
How do I connect my prep center to Seller Assistant?
Go to Integrations, select a suggested prep from prep centers section and enter your API token. Warehouses sync automatically on connection.
What happens if I unlink a shipment from a purchase order?
Unlinking deletes that draft shipment at the prep. The purchase order stays, and you can send it to another prep center.
What prep centers does Seller Assistant integrate with?
Seller Assistant integrates with 142 prep centers, most of them on PrepBusiness. See them by country and state in the prep center directory. Don't see yours? Request it in our roadmap.
Can I manage multiple warehouses and prep centers in one place?
Yes. Seller Assistant stores all warehouses and prep centers in a shared database. Each warehouse can be linked to a supplier and assigned to purchase orders individually.
How do I track inbound shipments sent to a prep center?
After send, the Prep tab on the PO shows received, damaged, and missing units, refreshed about every 30 minutes, plus the stage in the header, for example Receiving 52/60. Open the shipment at the prep center from the same PO. For a short or damaged line, claim from the supplier, the prep, or the carrier, accept the loss, or mark the units still expected, and add a note on the PO. Amazon inbound shipments created after prep stay in FBA Shipments.
Can I assign different prep centers to different purchase orders?
Yes. Each PO has an inline warehouse selector in the header. You can assign any synced or manually added warehouse per order.

Ready to connect your orders to prep?

Centralize your warehouses, sync your prep center, and send purchase orders to prep without leaving Seller Assistant.

Get Started

Not sure which plan fits your sourcing workflow? Chat with our team — we're happy to help.