Why won't Amazon accept my UPC barcode now that I have one for an existing product?


I’ve been selling my product on Amazon for a few months now, self-fulfilled because I didn’t have a barcode for it yet. Now that I have the barcode, I want to send inventory to Amazon for FBA.

I tried to duplicate this product and enter a new SKU and added the UPC # but it looks like it’s still the same product and when I go to ship the new listing for FBA, it says that the barcode must be Amazon’s. 1. I’m not sure Amazon won’t accept my barcode and 2. How should I set up my listing now that I want Amazon to fulfill? I tried deleting the second listing (the duplicate) but that just looks like I might delete the first one as well!

So confused…

Any help would be much appreciated!


did you try to convert the current listing to fba? it will give you a fnksu which is ‘amazons barcode’ when you go through the shipping plan and stuff.


Ok, I tried doing so with the first listing and I see the same issue as the duplicate listing. Based on why (in the tooltip box):
• the product IS new (all units are shrink-wrapped, brand new)
• I only applied the barcode to one listing so don’t think it corresponds to more than one ASIN ( I could be wrong).
• I don’t think Amazon would require this product to have an Amazon barcode because it doesn’t fall under a category where it should
• “The barcode doesn’t exist in the Amazon catalog”: do I need to input my barcode somewhere besides the product details?
• “This SKU is already assigned…” : I’m not sure if this is the issue or where to fix it.

Any thoughts?

Are you saying I should convert the listing to FBA anyway and then change my barcode status? I don’t want to use Amazon’s barcodes unless it’s free I guess, but my packaging shows my barcode so I’m not sure if that in itself is an issue if I choose to use Amazon’s barcodes.


It probably should be called an FBA Code instead because I think having Barcode in the name causes some confusion.

When there are (or could be) multiple sellers on a listing, Amazon uses this barcode to find the inventory from the appropriate seller to ship. You don’t want Amazon shipping your inventory when another seller gets the payment!

You don’t have to pay for these codes, you simply print out the barcodes Amazon provides as you are going through the FBA shipment process and affix them to your product making sure to cover up any other barcodes!

We purchase these labels to print Amazon codes on (ASIN B06XRJTR1C) which are the right size and formating for how Amazon formats the labels to print. They are 1 x 2-5/8 Inch 30 Up

Hope this helps - it’s not a big deal! Try pushing through (Convert and Send) and it will guide you to # of units, then next page (I think) is print labels!


Do you mean that the barcode Amazon provides will go on each unit? If so, why buy a barcodes at all? OR do you mean these are the barcode labels that go on the outside of each case of units? I guess it isn’t a big deal as long as Amazon provides it freely and gets the job done. I just want to confirm that’s what you mean before closing out this topic.

Appreciate it, thank you!


Hmmm - it might be best if you read through the FBA process - I don’t want to confuse you!

A UPC (or other identifier) is required to create a new listing on Amazon. This is required for different reasons that for FBA.

An Amazon Barcode is required to ship an item specifically for FBA. Amazon assigns these numbers. Each unit must have an Amazon Barcode on it. So, if you are shipping 5 units, the FBA process will prompt you to print 5 Amazon Barcodes. You then affix one to each unit making sure to cover up any other barcoding that might be viable.

Sometimes Amazon will allow you to use your own barcode, but that doesn’t appear to be the case for you so I won’t confuse things with that!

Again - I really think you should read the seller help section on FBA. It also goes through helpful information on packaging individual products and packaging boxes for shipment to Amazon. Seller forums are helpful - but it’s always best to go to the source!