What is a FNSKU label?

What exactly is a FNSKU? We have customers ask that question frequently. There is a lot of confusion among new sellers identifying the differences between FNSKU’s, ASIN’s, UPC codes, FBA labels and shipping labels and what they are, what they need and where they need it.


A FNSKU is Amazon’s barcode assigned to your product/ASIN. FNSKU stands for: Fulfillment Network Stock Keeping Unit and is unique to your ASIN/product and is issued by Amazon. 


Each product being fulfilled by Amazon is required to have a FNSKU code for Amazon to correctly identify the product they receive, as well as the seller it belongs to.


In order to obtain a FNSKU code from Amazon, your product has to have a UPC code. UPC codes are inexpensive and very easy to obtain, everything is done on-line, you can purchase from 1 UPC code to hundreds (as a packs). If you do a quick online search for UPC codes, you will find plenty of places where you can purchase them. No, you don’t need to be trademarked, you don’t need a US Company, it’s not super complicated or rocket science. It will literally take you around 5 minutes tops to get a UPC code.


When you are setting up your listing with Amazon, they will ask you for the UPC code in order to successfully create your listing. That is really the only place you will use the UPC code if you plan to sell on Amazon (you can only use 1 UPC code per item you will sell, you cannot use the same UPC codes for “garlic press” and “silicon spatula” each UPC is unique for 1 product). You will not print the UPC code anywhere on your product packaging if selling on Amazon.


Now that you have a UPC code you will be able to obtain the FNSKU that you will need to send to your supplier to add on your product packaging. Basically, you will download the PDF file with 30 per sheet FNSKU labels per sheet from you seller central account and forward that PDF to your supplier or to a 3rdparty inspection service like us to apply on your product packaging.


You can apply the FNSKU label as a sticker or have it printed on your product packaging. Keep in mind that if at some point down the road you would like to sell your products outside Amazon, you will need to swap out the FNSKU code with the UPC code, you cannot have both on your package if you sell on Amazon. When selling on Amazon you can ONLY have the FNSKU code visible, you cannot have any other barcodes on your product packaging other than the FNSKU. 


Amazon requirements for FNSKU’s are:


  • Barcodes must be printed on white background with black ink

  • Non-reflective

  • 1inch x 2 inches and 2 inches x 3 inches (1 inch x 3 inches or 2 inches x 2 inches, for example).

  • Must remain scannable for at least 24 months (DO NOT USE ink printers or cheap tonner’s etc.)

  • Must contain the FNSKU code under the barcode (X00........)

  • Product Name (garlic press)

  • Product Condition (new)



Things to avoid:

  • Do not print your FNSKU directly on a polybag/opp bag 

  • Do not print your FNSKU on black background with white print



We hope this helps you identify what a FNSKU is. Remember, if you sell on Amazon, the only barcode that should be present on your packaging is the FNSKU, no other barcode should be visible.


We will discuss / explain about the other “codes” (FBA labels, Shipping labels, ASIN) in a future post.