Sell on Amazon Sign in
This article applies to selling in: United States

Receiving inventory into FBA Onsite

Can I leave my inventory where it is and assign it to my FBA Onsite location?

No. When you combine your FBA Onsite inventory with your other warehouse inventory, it does not meet the Terms and Conditions for participation in FBA Onsite.

There must be a designated area in your site dedicated to Onsite operations including storage, picking, and packing.

Note: Per the program terms and conditions, Amazon reserves the right to audit any FBA Onsite facility during normal operating hours.

What is the item limit for my FBA Onsite location?

There is a required trial period where a limited number of products can be received and fulfilled daily. The trial period lasts at least the first week of enrollment in the program. Your trial period receiving limit is discussed when you launch your site.

After the trial period, you can receive up to 50,000 units per FNSKU using the warehouse management system (WMS).

If you reach this limit and you want to increase it, please contact FBA Onsite Seller Support.

Are there size or dimension restrictions for FBA Onsite?

You can fulfill items that are the same size tiers as traditional FBA, with the exception of Special oversize such as pallets or other items that requirespecial handling.You cannot fulfill these throughFBA Onsite at this time.

For more information, see Product size tiers.

What is the difference between ASIN, SKU, and FNSKU? Which one do I use for scanning my items in WMS?

In the WMS, use FNSKUs or UPCs when receiving inventory into your Onsite facility.

  • An ASIN is an Amazon Serial Identification Number. When several sellers sell the same product, they share the same ASIN. For more information, see the ASIN Creation Policy.
  • A SKU—or merchant SKU—is the unique identifier you create for your product.
  • A UPC is a Universal Product Code used in the US and other countries. Many products come with a UPC barcode already attached. For more information, see Product UPCs and GTINs.
  • FNSKUs are unique identifiers for both the product and the FBA product listing. These automatically generate when you create FBA listings.

How do I print FNSKU labels?

First, verify that your offer is an FBA listing. Creating FBA listings generates the FNSKU.

To print FNSKU or UPC barcodes in Seller Central, go to Inventory > Inventory Management > select Print Item Labels from the drop-down for your listing. Next, select the label quantity and size you want to print.

For more information, see Use an Amazon barcode to track inventory.

How do I receive inventory into my FBA Onsite location?

Go to the WMS > Inbound > Receive Product > scan the FNSKU > select a Purchase Order ID > enter the requested details > stow the item in the specified container.

You should see an automated Purchase Order (PO) in the WMS within 30 minutes of creating a new FBA listing in Seller Central. If you do not, your product may not be eligible or it may be missing dimensions.

Note: Do not use the ‘Found’ function. It does not process your inventory and your items will not show up for sale on

I see a PO for 50,000 units in the WMS. How was that created?

Our system automatically creates POs for FBA Onsite locations in the amount of 50,000 units for qualifying FBA listings. This is for your convenience. You are not required to use all or any of the 50,000 unit POs.

Note: The automated POs are for FBA Onsite receiving only. They do apply to traditional FBA inventory shipped to Amazon fulfillment centers.

How long after creating an FBA listing can I begin to receive inventory using the WMS?

If your product meets FBA criteria, and you have entered product weights and dimensions into the system, it will take about 30 minutes for POs to generate. Once you have them, you can process inventory in the WMS.

Note: During peak and holiday periods, this can take up to two hours, or, in rare cases, up to 24 hours.

I created a new FBA listing. Why don’t I see a PO for receiving it in the WMS?

POs do not generate for products that are:

  1. Not eligible to sell on Amazon
  2. Missing package dimensions, weight, or other information required to process inventory in the WMS

If your items do not fall into one of these categories, please verify that you created a Fulfillment by Amazon (FBA) listing.

If you created an FBA listing, but did not receive an automated PO for your FNSKUs, you can either contact Seller Support or make an item-level update to your listing.

Go to the Vital Info, Description, and More Details tabs to make item-level updates. Once you edit and save in the WMS, you should see a PO for the listing’s FNSKU in 20-30 minutes.

How can I update weights or dimensions for my products?

To update package dimensions or other item details in Seller Central, see Correct an Error on a Product Detail Page.

Will previous listings automatically generate new POs?

Yes. However, if you have a listing that was previously merchant fulfilled and you recently converted it to an FBA listing, it may not have generated a PO.

You can trigger automated shipment creation for an existing listing by making item-level changes on the Vital Info, Description, and More Details tabs of your listing.

Once you make an edit and save, you should see a PO for the listing’s FNSKU in the WMS within 20-30 minutes.

How will automated POs affect the rest of my shipments to FBA?

If you are also sending shipments to Amazon fulfillment centers, follow the standard process. Automated POs are only available for use when receiving into your Onsite location.

I have several FBA Onsite locations. Will they all generate automated POs for receiving?

Yes. POs generate for each site registered to your account. Each site has its own limit of 50,000 units per FNSKU.

Sign in to use the tool and get personalized help (desktop browser required). Sign in

Reach Hundreds of Millions of Customers

Start Selling On Amazon

© 1999-2022,, Inc. or its affiliates