There is so much jargon to sell on Amazon. The focus is to go through product identifiers like UPC code, EAN, ASIN, and SKU. The emphasis here will be on seller SKU for Amazon.

Having a unique SKU on your product helps you identify, manage and track inventory levels across different Amazon marketplaces.

This article will demystify what a seller SKU on Amazon is, how to use it, the difference between SKUs and other product identifiers, and what to consider when you create seller SKU.

Seller SKU for Amazon? Why?

SKU stands for Stock Keeping Unit and is often pronounced as “skew.” It’s simply a bunch of letters, numbers, characters to use to identify the product. Think of it as a name, but it has to be unique to track and manage inventory.

When sellers talk about Amazon SKU, there are 2 things it could be:

1. the actual SKU of the product to identify it on the Amazon platform
2. or FNSKU

In the world of Amazon, when you create a product listing, you can choose to enter your own SKU for Amazon or you can leave it blank and let Amazon auto-generate one for you.

However, when it comes to FNSKU, it is a unique SKU for Amazon and is not used anywhere else in the retail world. Amazon can only create and use it.

You cannot create or edit a FNSKU. It is unique. It is fixed. It cannot be changed.

A regular SKU could be something like HYUED-73943-AMZ for Amazon. The exact same product could have a SKU HYUED-73943-WMT for Walmart.

However a FNSKU starts with X00 and looks something like X00349JD3. This identifies which seller the product belongs to. Many sellers on Amazon sell the same product, so this FNSKU is a way to identify who is selling the product.

The reason you need a seller SKU for Amazon?

Aside from helping you achieve better inventory management, understanding the other benefits of seller SKU will help you become a better seller. Some of the other benefits of seller SKU are:

Product tracking

Amazon uses seller SKUs for product sorting, packing, and internal tracking. In other words, a functional SKU system helps the eCommerce giant to monitor warehouse transfers so that confusion doesn’t set in. 

A functional SKU system makes it easy for Amazon’s fulfillment center workers to pick, sort, arrange, and ship products. When paired with a specific merchant’s product identifier like UPCs, a functional SKU system makes it easy for Amazon to monitor sales across its marketplaces. Amazon-generated SKUs are used to allocate Best Sellers Rank. 

Data management becomes easy

One of the benefits of creating seller SKUs for your products is that while working on your spreadsheets, they will tidy up your data and make them easy to read. It lets you track stock levels of products, sales trends, profitability, warehouse transfers, and consumer spending habits. 

They are also useful when you use an inventory management system to streamline your supply chain. An inventory management system is designed to work best with shorter inputs. For instance, an inventory management tool will prefer to work with codes like HNB-DS50W rather than full product titles. 

Improves Communication with Vendors

Amazon seller SKUs also help to streamline communication between sellers and suppliers or vendors. Creating an SKU for your product makes your correspondence or memo short and easy to comprehend. You won’t get to mention the full product titles and their unique features/benefits in your invoice, message, or email to your vendors. Ultimately, Amazon-generated SKUs will keep your correspondences concise and time-efficient.

Helps with easy product identification 

An SKU makes it easy to identify your products and product categories, especially when your inventory has several products with multiple variations. You can represent your product titles and features using an SKU, making it convenient to manage your inventory. For example, if you sell catalyst PON 4-Port PoE voice-activated, you can use “P-4P-P-VA” to represent the product in your inventory sheet.

Amazon uses seller SKU to match products with corresponding product detail pages

One of the reasons why Amazon makes seller SKU an obligation for every seller is that the company uses it to match products with corresponding product detail pages on its catalog. And that’s why if you refuse to create and assign SKUs for your products, Amazon will take it upon itself to generate random SKUs for your products for proper product-product detail match. 

Difference between Amazon seller SKU, FNSKU, barcode, UPC, and ASIN

Here, we will look at how seller SKU compares with FNSKU, barcode, UPC, and ASIN.

Amazon seller SKU vs FNSKU 

On the other hand, FNSKU is an acronym for Amazon Fulfillment Network Stock Keeping Unit. It’s a terminology that describes the barcodes on products or goods shipped through Amazon FBA (Fulfillment by Amazon). So, if you use the Amazon FBA program, Amazon will ship your products with the FNSKU code on them to identify it belongs to you and not another seller.

Therefore, you must add FNSKU codes to your product label before sending them to Amazon fulfillment centers. Since Amazon handles many products (in some cases, similar products), it’s essential to generate FNSKU for your products so that they’re attributed to your business. FNSKU also lets you get any income that’s due to your account from sales on Amazon. 

Amazon seller SKU vs UPC 

UPC stands for Universal Product Codes. It’s a numeric barcode generated and assigned by product manufacturers for product identification. You need the UPC of a product to be able to list it on Amazon. UPC makes it easy for Amazon users to identify the manufacturer of a product and the store they come from. 

On the other hand, a seller SKU is a special alphanumeric code generated and assigned to products in a seller’s inventory for tracking and inventory management purposes.

Amazon seller SKU vs ASIN

ASIN is an acronym for Amazon Standard Identification Number, and it’s also a code generated by only Amazon to identify products in its over 13 marketplaces. Unlike seller SKU, ASIN is always visible to every Amazon user on the listing page. 

Please note that one ASIN can have different SKUs, usually when a product has multiple variations.

Amazon seller SKU vs barcode

SKU and barcode are similar in some ways, but they are not the same due to how they are assigned to a product. While a seller SKU is unique to a seller or business, barcodes are used universally. They are assigned to similar products regardless of the marketplace the products are sold. For instance, a hairbrush in the Indian and Italian marketplaces will retain one barcode but different seller SKUs. 

What makes up a SKU?

If you intend to have a small number of products, make your SKUs descriptive. If not, do NOT use identifiers in SKUs. For small catalogs, consider the following:

• Product name: Your product title should be captured in the SKU. For example, cell phone covers, vacuum cleaners, and shirts. 
• Product category: You can create a category for related products. For example, you can categorize products like socks, shirts, and bibs into “clothing or apparel.” 
• Product condition: The SKU should capture the physical condition of the product. E.g. open box, used, or new.
• Product supplier: Include the brand or vendor you sourced your products from.
• Product features: Color, size, material/ingredients, and other prominent features should be highlighted in the SKU. 
• Cost: The purchase price should also be included in the SKU.
• Seasonality: You also state the season (whether winter, summer, or during holidays) the products are better sold.
• The sequence or batch number: The product sequence number in which the products are added to the inventory should also be contained in a seller SKU.
• Any applicable variations like the product sizes or colors. 

Amazon seller SKU rules

It would help if you stuck to some rules when creating SKUs for your products. These rules include the following:

• All products listed on Amazon must have an SKU, which will be a maximum of 30 characters. Anything longer than 30 characters will make it difficult to interpret.
• The SKUs assigned to your product cannot be identical; they must all be unique. For example, if you have ten products in your inventory file, you must generate 10 SKUs for the ten products. 
• It’s impossible to change an existing SKU without deleting the product listing. Anytime you want to modify your product SKUs, you must delete them and create a fresh listing. 
• You can reuse SKUs after completely selling all the products in your inventory file. 
• Please don’t use any part of the manufacturer’s numbers within your product SKUs to prevent confusion. It’s best to approach SKU creation using a formula/generator to avoid haphazard creations. 

How to make a product SKU & an example

Here’s a guide on how to create or generate a good SKU for your product:

• The first two letters should represent your manufacturer or supplier. If the manufacturer’s name is Texas Instruments, the first two letters of your product SKU should be “TI.”
• The next two letters should represent the product type. For instance, selling video games from Texas Instruments, the next two characters can be “VG.” 
• Write the date you sent the product to Amazon fulfillment centers. If you date you sent the product is 05/10/2022, then use 05102022.
• The next step is to indicate the condition of the product. If it’s a used product, enter “UP,” but if it’s a new product, then use “NP.”
• Enter the price you purchased the product from the vendor or manufacturer. You can use something like 100D if the price is $100. 
• You can then use sequential numbering to complete your product SKU (something like 001, 002, 003). Remember, your SKU should not be more than 40 characters; the shorter, the better.

The SKU from the steps above should be something like this: TI-VG-05102022-NP-100D-001. If you have followed up with the steps, you should be able to deduce the product SKU as follows:

• TI: Manufacturer name
• VG: Product title
• 05102022: The date the product was sent to the Amazon fulfillment center.
• NP: The physical condition of the product. Here, it’s a new product.
• 100D: The purchase price of the product from the manufacturer.
• 001: The batch number for easy tracking.

Proper SKU management – best practices

Here are a few things to get right when creating SKUs for your products. Some of the best practices include:

#1. Generate SKUs by yourself and not allow Amazon to do it for you

I have mentioned several times the need to generate SKUs by yourself and not allow Amazon to generate a random SKU for your products. Generating SKUs for your products by yourself makes it easy to identify your product categories and expand them as necessary. 

#2. Use SKU Generator

You can’t possibly sit down in the comfort of your office to generate SKUs for 100 products. Aside from fatigue, mistakes can set in. At best, you should use an SKU Generator; it makes the process easy and fast. Some great SKU generators on the market include Gorgias, TradeGecko, Zoho Inventory, and Sellery. 

#3. Ensure your custom SKU format is consistent

Another best practice is to maintain a consistent SKU format. Start by creating a standard format. Then, stick to this format when generating your product SKUs to keep the codes consistent.

#4. Avoid starting your product SKU with the number 0

Starting your product SKUs with 0 can create confusion because some inventory management software can interpret zero (0) as “nothing.”

#5. Begin your product SKUs with letters

Your product inventory’s first two or three characters should represent the highest category. So, begin your product SKUs with letters but avoid using letters that look like numbers (for example, “I” can appear like “1.” Additionally, keep your product SKUs as short as possible but don’t overload them with meaning. 

Final Thoughts

Amazon SKUs, one out of many product identifiers, come in handy to enable you to manage your inventory better and provide seamless customer service to your customers. With a sound knowledge of how SKUs work and how to create them, browsing through your product listing will be more user-friendly. Using SKUs to describe your products and their unique attributes instead of writing a long product title and explaining the different features makes it easy to get insights from your data spreadsheets and also utilize inventory management tools. 

You can either choose to create your SKUs, or Amazon will generate a random code for your products. Creating your SKUs will allow you to generate a comprehensive product identification system, making tracking and managing your inventory easy. 

I advise that you find time to create your own seller SKU because allowing Amazon to generate a random code for you has far-reaching disadvantages. One of the biggest disadvantages is that the SKUs will be meaningless and difficult to recall when you need them for inventory management. 

As you optimize your product listing and assign SKUs to your products, if you have any challenges or questions, don’t hesitate to contact me for prompt assistance using the comment below.