FNSKU 101: The Ultimate Guide for FBA Sellers on Creating Amazon FNSKUs

April 10, 2024 From Zero to FNSKU Hero: A Comprehensive Tutorial for Amazon FBA Sellers

The term Fulfillment Network Stock Keeping Unit (FNSKU) is unique to Amazon and refers to barcodes that play a crucial role in product identification and tracking for sellers.

 Similar to a UPC, FNSKUs are utilized by Amazon to label your products in their fulfillment centers.

 These labels are vital as they ensure you receive proper credit when Amazon delivers your product to a customer. 

However, for new sellers, understanding Amazon’s FNSKU labeling systems can be confusing. 

In this article, we will provide you with comprehensive information to help you navigate and comprehend the FNSKU labeling process on Amazon.

What is an FNSKU?

FNSKU, or Fulfillment Network Stock Keeping Unit, is an Amazon detailed barcode used by the FBA sellers.

Amazon used this barcode to track sellers’ inventory in their fulfillment centers. It allows Amazon to identify an item with its seller. 

It is not like another barcode that is used by other e-commerce platforms. Amazon FNSKU is exclusive to goods sold on Amazon while using their fulfillment centers.  

What does it look like?

FNSKU barcode contains:

  • Scannable barcode
  • Product Description
  • ASIN
  • Product condition

Importance of Using Amazon FNSKU:

Amazon customizes FNSKU to design product labels. It serves the unique purpose of your product. However, there will be a chance for the same product but a different seller.

If you’re using the same UPC to ship the same product, they will likely ship together. To avoid confusion, Amazon desires all sellers to include the FNSKU on the product’s shipping label. This makes it easy to match each product to the appropriate reseller. 

Amazon only supports products that have an FNSKU barcode. It should match with the ASIN, where no extra label is needed. It is less expensive and easier.

Should we use FNSKU labels?

FNSKU is to be used by all FBA resellers. In particular, trademark owners who are sellers in the trademark register.

Using FNSKU makes monitoring inventory across the Amazon ecosystem easy and troubleshoots issues ranging from inventory leaks to intellectual property violations.

To get this barcode, amazon sellers must add FNSKU labels to every package sent to Amazon. If you use UPC or skip this part, your product sent in can be conflated. 

What are the benefits of using it?

Amazon customizes FNSKU to design product labels.

It serves the unique purpose of your product.

However, there will be a chance for the same product but a different seller.

 If you’re using the same UPC to ship the same product, they will likely ship together.

To avoid confusion, Amazon desires all sellers to include the FNSKU on the product’s shipping label.

This makes it easy to match each product to the appropriate reseller. 

Amazon only supports products that have an FNSKU barcode.

It should match with the ASIN, where no extra label is needed. It is less expensive and easier.

How to create an Amazon FNSKU?

Follow the below steps to create an FNSKU in Amazon seller central.

Step 1: in the central seller page, you can see the settings option; choose fulfillment by Amazon.

Step 2: select FBA product barcode preference from the drop-down list and click on edit

Step 3: Select the Amazon barcode and click on update

Step 4: select manage FBA inventory from the inventory drop-down

Step 5: Upload the latest product

Step 6: Return to the managed FBA inventory after listing and check whether the FNSKU was added.

How to print FNSKU labels?

Step 1: from seller central, visit inventory and choose to manage inventory.

Step 2: Select the item you need to print the label for.

Step 3: Select print item labels.

Step 4: Choose the size labels and print. 

Step 5: apply this to your products. 

What are the major differences between FNSKU and ASIN?

Comparison between FNSKU and ASIN

ASIN is short for Amazon Standard Info Number, and every product on Amazon is associated with a number.

This can be seen on the product page or in the URL.

They are also clearly listed in the dealer catalog, SKU, and FNSKU.

The ASIN is also an Amazon-specific inventory identifier, but multiple retailers can join the ASIN since product detail pages are shared between multiple retailers.

So, the major differences are:

  • Each seller and each product have different FNSKUs.

It is important because if other FBA sellers sell the same goods on Amazon, it helps discriminate which sellers sell which product.

  • Items without FNSKU will be mixed with other goods of the same ASIN in FC.

They can also be dispersed and shared on CF across the state.

For example, you could win a Buy Box and sell a product to a customer.

Still, instead of choosing and packaging your item, it could be your competitor’s product, meaning Amazon will credit the other seller for you. 

  • However, this can be problematic for large brands or ASINs where several retailers compete for the same ASIN.

While Amazon is more aggressive in fighting counterfeits, FNSKUs can help determine the responsible seller or item.

However, mixed inventory without FNSKU can prevent Amazon from attributing issues to the correct reseller.

FNSKU thus ensures that genuine sellers offering genuine products don’t experience account issues.

This can range from negative reviews to goods or account bans.

Amazon has gone a step further with the Amazon Transparency program, an item serialization service worth considering if you’re an FBA seller and have issues with counterfeiting.

  •  The FNSKU is also particularly useful when a product is lost, as it allows the product to be traced and the lost inventory paid to the correct merchant account.

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What are the major differences between FNSKU and UPC?

Universal Product Code is the barcode you see on most retail products.

It is a barcode-encoded GTIN, similar to the EAN and ISBN barcodes. Outputs UPC and other commonly accepted barcodes.

UPC cannot be used as the unique identifier for retail and wholesale sellers as it is similar for the same products.

On the other hand, FNSKU is the best option for amazon sellers as it is unique.

What if my item does not have an FNSKU barcode?

If your product has a unique UPC or EAN under your brand, you can opt out of FNSKU.

However, Amazon still has the right to stop processing shipments if it does not have FNSKU.

Therefore, it is always better to mark your product with FNSKU, even if it has a unique EAN number.

On the other hand, if you sell a joint product that is also sold by many others, you need an FNSKU.

Otherwise, your inventory will be mixed with all other items with similar EAN numbers and thrown into the same bin.

Sellers never want to co-mingle for their inventories.

The poor handling not only damaged the packaging but also the product.

Without the Amazon FNSKU label, your product can get mixed with another seller’s model.

It also helps to prevent fraud. 

Is it mandatory to use the FNSKU barcode?

No, it is not mandatory, as amazon never forced you to use the barcode for your inventory. 

But there are some rare occasions where you need to use this, such as selling consumable products. 

In most cases, you can choose whether you will add the barcode. 

What are the Advantages of using the FNSKU barcode?

Some of the main advantages of using FNSKU barcode include: 

Avoid commingled stock:

The most significant advantage of using FNSKU is that Amazon keeps tracking your specific products within its fulfillment procedure, meaning you can avoid commingling stock.

Commingling stock means when several sellers store the same item with a similar manufacturer barcode in the fulfillment center of Amazon. 

This mixed-up inventory is not a problem for wholesale sellers or who have an arbitrage business model.

FNSKU avoids this problem, and it is the main reason why it’s a recommended course.

Save money:

Another supplemental advantage is that it is free.

Where you need to pay an EAN number or UPC to your item, you don’t need to add any scannable barcode.

What are the disadvantages of using the FNSKU barcode?

There is only one minor disadvantage of using FNSKU labels;

FNSKU is not for retail:

If you want to grow your private label brand and take your goods into retail stores one day, you won’t be able to add an FNSKU barcode as your ID label.

Instead, you can use a manufacturer barcode.

Where to find an FNSKU? 

Before getting an FNSKU, you must ensure that your product is FBA, not FBM.

Amazon assigns you ab FNSKU when you launch your product and catalog the item.

You must export the barcode and add the FNSKU label to your product packaging label. 


You need to know these things to label the FNSKU on Amazon. With this barcode, you will get paid after your product gets sold. If the barcode is missing or there is any mistake, you will not get paid even after your product sells. So it’s important to add this to your product packaging labels. 


Questions About
FNSKU on Amazon

What are the label requirements for FNSKUs on Amazon?

Amazon has specific standards for labeling products with FNSKUs. Sellers can find detailed guidelines and label requirements in the Amazon Seller Central platform to ensure compliance with labeling standards.

What is the difference between an Amazon barcode vs manufacturer barcode?

An Amazon barcode refers to the FNSKU barcode used by Amazon for internal tracking, while a manufacturer barcode is typically a UPC or EAN barcode provided by the product’s manufacturer for general retail purposes. The two serve different functions within the Amazon ecosystem.

Should I use an ASIN label or an FNSKU label on my products?

For products sold through Amazon’s fulfillment network, it is necessary to use FNSKU labels. ASIN labels are not used for tracking and fulfillment purposes within Amazon’s system.

What are the Amazon barcode requirements?

Yes, Amazon has specific barcode requirements, including the use of FNSKU labels for products sent to their fulfillment centers. Sellers should familiarize themselves with Amazon’s barcode requirements to ensure compliance.

How much do you charge?


Please visit our pricing page to learn more. 

Do you require a certain number of orders per month?


It depends.


We value your business and like to make assessments on a case-by-case basis, so we can find the best fit for your requirements.


In most cases, if you’re doing over 100-200 orders per month on Amazon, you will qualify to use our Amazon FBA order fulfillment services. 

Didn’t find your answers? Contact us

Blair Forrest

Blair Forrest

Blair Forrest is the CMO of AMZ Prep. Blair helps provide consulting and guidance through our articles, guides, and other resources to help growing eCommerce & Amazon FBA businesses master their logistics and fulfillment.

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