Amazon: Getting Started and Managing UPC/ASIN Mismatches

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Selling On Amazon With Inventory Source

Thank you for choosing Inventory Source for all of your Inventory Automation needs. This is a guide to help you sell on Amazon using Inventory Source. Amazon is an incredible marketplace with millions of purchases made daily. Our Inventory Automation Service makes it easy to load thousands of products to your Amazon store and keep the product pricing and quantity updated daily. For those sourcing products from US Direct, at the end of this article we provide some helpful information specific to this integration in our FAQ's.

Before you get started...

We know you are excited to begin loading products to your store, and you do have the option to simply load all your supplier's products to your Amazon account in the click of a button. However, it is important to know we HIGHLY recommend against loading all your products at once, due to the potential for what is referred to as UPC/ASIN Mismatch issues.

To identify potential UPC/ASIN mismatches, our recommended process is to load products slowly and review them in batches as outlined in our recommended uploading process at the bottom of this article. 

We also suggest going through and excluding all products or brands that may be red flagged on Amazon due to their restrictions. A list of their restrictions can be found within all of these links:

-> Skip to our recommended product uploading process. <-

Wait.... What?! 

- Load slowly? 

- Wrong products showing?

- Wrong product size, quantity, type?

Check for UPC to ASIN Mismatches!

Let us explain...



What are Amazon UPC/ASIN Mismatches?

When products are loaded to Amazon, they are loaded by UPC and Amazon then assigns product details to the loaded product. No matter what data we send to Amazon they will load their own data if they have the UPC stored in their database. In some cases Amazon "assigns" the product you've loaded to the wrong Amazon ASIN. An Amazon ASIN is the unique identifier number that Amazon has created for internally identifying products. 

This is more common in products that come in different sizes and variations of the products. For example, Amazon can often have the same UPC stored for a pair of standard binoculars, the XL binoculars that are more expensive, and the combo pack that is much more expensive.  More specifically, Amazon will take the UPC and choose an ASIN that it has determined to be most fitting. 

A "Real World" UPC/ASIN Mismatch Example:

The following is a common item sold on Amazon: UPC# 010343829923

When you search for this UPC on Amazon, you will oddly see more than one result with greatly differing prices, such as follows:

CLICK HERE to open up this specific page.

Why are there different prices for the same UPC? 

After all, a UPC is a Unique identifier right? How can the same product have wildly varying prices? Well, if you look closely, you'll see it's because there are different quantities in each product listing. Notice how some are a 2 packs? This is where the issue is. Sometimes products sold in different quantities have the same UPC. So a 2 Pack will have the same UPC as a 1-pack. 

Additionally, even though these products have the same UPC, Amazon will assign the UPC to two different ASIN's based on the quantity in the bundle. Here is this example:

UPC: 010343829923 (1 Pack, 20 sheets each) -> ASIN: B005GQW0OW, Price: $48.29

UPC: 010343829923 (2 Pack, 20 sheets each) -> ASIN: B0032JWG1W, Price: $92.58

These items have the exact same UPC! This one is a case of 5, selling for $223.24 -

To make matters more challenging, when Inventory Source loads these products to Amazon, sometimes Amazon doesn't know where to put the item. Amazon guesses whether the item is a 1 pack or a 2 pack. Occasionally, they guess wrong and as you can imagine, this leads to issues. When Amazon guesses the ASIN incorrectly, your 2 pack could easily be listed at the cheaper price of the 1 pack. See where I'm going with this? Now, Amazon customers are going to think they've found a great deal. They think "Wow, this guy is running a sale!! Buy everything!". Then by the time you realize what happened, you have already received 30 orders for the incorrect price. Bummer. 

This scenario is exactly why we suggest you load your products slowly. You need to manually review each product (after upload) individually to determine any mismatched ASINs Amazon matched for the UPC.

Yes, this is time-consuming... and it is unfortunate but it is very necessary given the current way Amazon matches UPCs... at least you didn't miss 25 ASIN mismatches by loading them all at once.


How to overcome this ASIN/UPC Mismatch Issue?

Answer: Follow our Recommend Product Uploading Process... *Follow this process BEFORE you set your feed to active and load ANY products*

Recommended Product Uploading Process:
  1. Login to your Inventory Source Dashboard to access Catalog Manager.
  2. Add a small batch of products from your feed to your catalog. We recommend adding 100-200 products at a time.
  3. Set your feed to active. The Inventory Source app then loads the products in your catalog to your store on the next sync.
  4. Review the products on your store. Check the titles, descriptions, etc. and identify any ASIN mismatches.
  5. For products with mismatched ASINs, update them directly in each product's "customize" section in Catalog Manager. See how here.
Correct Mismatched ASIN Method #1: As you find mismatches, if you would prefer to manually match up ASINs and provide the SKU to ASIN matching in a spreadsheet, we will overwrite the "UPC matching" process and upload the products by the ASINs you provide. Here is an example of the format spreadsheet we would be expecting. Use the bulk upload process within your Category Manager to accomplish this.

Correct Mismatched ASIN Method #2: As you find mismatches you can simply update your listing with the correct information (title, image, etc.) on Amazon manually in Seller Central. We will not overwrite this information after initial upload.

Now, the goal is to keep adding products. Eventually your store will have thousands of products, but it takes a while. The best thing you can do is take your time but also commit to building your product list. If you wait, your list won't grow and you won't get sales. 

How can I prevent fulfilling orders with ASIN Mismatch issues?

Answer: Follow our Recommended Order Quality Check Process...This process will allow you to catch orders where titles do not match before processing. 

Recommended Order Quality Check Process:

  1. Login to your Inventory Source Dashboard to access Catalog Manager.
  2. Open your order and view line item details.
  3. Compare supplier product title below the imported platform product title to aid in quickly determining SKU/ASIN/UPC mismatches.

Frequently Asked Questions:

What is the difference between a UPC and an ASIN?

A UPC is a "Universal Product Code", which is essentially a universal product identification number used across the entire world. The purpose of the UPC is to ensure that every product in the world has it's own unique number, and therefore can be identified by businesses in different industries, different countries and different marketplaces. However, Amazon ASINS, or "Amazon Standard Identification Number" is specific to Amazon. Companies other than Amazon don't use ASIN's as unique identifiers, because UPC's already exist. Additionally, Amazons ASIN system isn't perfect. New products are created by people all the time and Amazon doesn't have the best grasp on which products are assigned which ASIN. However, due to Amazon's popularity, many people and businesses are forced to deal with Amazon's ASIN issues.

Why doesn't Amazon fix this issue?

This issue stems from a number of other issues. Namely, sometimes sellers create their own product listings and incorrectly use UPC's and ASIN's to identify products they sell. Amazon is big, but it takes an incredible amount of oversight to ensure every product is assigned correctly. To extend that, at Inventory Source, we get the product data from your supplier. If your supplier doesn't provide ASINs by default in their product data, then we are at the mercy of Amazon to assign the product UPC's to the correct ASIN. Unfortunately, this doesn't always happen as we hope.

Why doesn't my supplier fix this issue?

Most suppliers have little incentive to take on the hefty task to managing and maintaining accurate ASINs, they leave this job up to the retailer. The retailers that put in the time and effort have all the incentive to do so as they can sell more and retain a better seller rating than their competitors.

What should I know about ASIN Mismatches with my US Direct integration?

US Direct provides online retailers selling on Amazon easy access to over 200,000 products with more than a dozen niche categories, giving you a wide variety of products to choose from when selling on Amazon. But just because you have access to all of these products does  NOT mean that you should list all these products on Amazon. We have many customers that are successfully sell on marketplaces today.. However improve your chance of avoiding ASIN mismatches, it does require you to be selective with listing products and following the rules on how to overcome ASIN Mismatches (see previous section).

As the retailer, it is your responsibility to ensure the products are not subject to ASIN Mismatches, as well as perform your due diligence to make sure the products you list on Amazon do not require authorization from the brands before attempting to list them. To learn more about our marketplace policies, please see US Direct's Marketplace Disclaimer.

There are some categories that are higher risk of ASIN mismatches. Below is a list of category we recommend you exercise caution when listing on Amazon:

  1. Jewelry
  2. Beauty & Fragrance
  3. Bulk General Merchandise
  4. Skate Apparel Shoes & Gear
  5. Women's Fashion Apparel 

How many UPC/ASIN's mismatches can I expect to find?

Usually, we find about 1% of items or less have ASIN mismatches. The number is very low. However, if you are listing tens of thousands of products on your store, then 1% can seem like a lot! 
Imagine if you load 5,000 products to your Amazon account and only 0.5% (a half of one percent) of the products have ASIN mismatches. That's still 25 products that will have ASIN issues and if Amazon customers purchase these products, then you will have issues to deal with.

Can't I just load all the products and deal with the issues later when they arise?

It's your business, you're free to do what you'd like. We suggest loading the products slowly, or at least as carefully as possible to avoid issues. 

I already have an Amazon Seller Central account, but I can't get my developer/API auth token. What do I do?

Amazon has different levels of accounts. The individual plan and the professional plan. You need to access the professional plan.

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