Stock numbers (SKUs) for eCommerce

Choosing stock numbers is on the face of it a pretty uninspiring subject. However, all online retailers need to do it and choosing the wrong format can cause lots of pain later. Here are some quick tips:

Avoid preceding zeros

Avoid zeros at the front of your stock numbers like the plague. Excel will strip them out automatically causing endless issues when you are trying to combine spreadsheets of data. 

This can cause issues if you are using barcodes as your stock numbers as these frequently have zeros at the front. An EAN (European Article number) is officially 13 characters long and so an 11 character EAN should really have two zeros at the front.

Advice: If you want to use barcodes as your stock numbers, I suggest you add a prefix e.g. Brand-Barcode Avent-0123456789898

Don’t just use numbers

If you just use a number string as your stock number, then this will mean that this number can be treated in two different ways by excel.

1.      As a string of digits i.e. plain text

2.      As a number

From Excel’s POV these are NOT equivalent. This will cause problem if you are trying to combine spreadsheets or use functions like VOOKUP as what looks like the same stock number will not match.

Advice: As above, start your stock number with text, that way it will ALWAYS be treated as text.

Avoid special characters

Keep to numbers and letters and limited punctuation in stock numbers as special characters can cause issues. For example Amazon does not support apostrophes. Also, apostrophes come in multiple formats which look similar e.g. straight, curly.

Include variant information

If you include variant information in the stock number e.g. Avent00100-Blue, Avent00100-Pink, you can use the root stock number to filter for variants.

Include useful information

Bit more subjective this, but personally I would always include useful information such as brand in the stock number as it makes filtering easy.

Barcodes for eCommerce

Barcodes are much abused by a hugely important aspect of retail, especially eCommerce. They (should) uniquely identify products and are a vital part of the process of listing products and processing orders.

This article looks at the advantages of using barcodes and the pitfalls that can arise.

Types of Barcodes

Barcodes come in several flavours. The main ones are EAN (European Article Number – 13 characters) and UPC (Universal Product Code – 12 characters).  In the UK EAN is most used.

Sometimes barcodes are less than the specified number of characters and these missing digits can be shown as proceeding zeros e.g., 0000123456789 not 123456789. This can cause product with marketplace matching as some marketplaces require the full thirteen characters to make a match.

Barcode issuing

Valid barcodes are issued by GS1, a global standard authority. A manufacturer must buy a licence to issue barcodes for their products and digits 2 to 6 of the barcode signifies the manufacturer.

Advantages of using Barcodes

Identifying products

If you have recorded the barcode for each product in your system this can be used for identifying products during common warehouse functions such as:

  • Booking in deliveries
  • Dispatching products
  • Stock taking

Marketplace matching

Marketplaces such as Amazon, CDiscount and OnBuy are catalogue-based systems that organise products by barcode. Creating a new product will require a barcode in most categories. Similarly, to list a new product the quickest method is to search the catalogue by barcode and if a match is found specify a price and quantity.

Pitfalls of using barcodes

The problem with listing or dispatching products based on their barcode is generally due to their misuse by suppliers.

Assorted colours

Frequently products are delivered in a box of assorted designs or colours which all have the same barcode. Great for a physical shop but not so good online where customers expect to get EXACTLY the product they see in the image.

Updated/refreshed products

An updated product should get a new barcode, but suppliers frequently reuse barcodes. If the retailers is matching product by barcode, they may not realise that the product has changed and send out the new product when the customer is expecting the old product.

Incorrect issuing

As mentioned above, valid barcodes are not just a string of numbers but are issued by GS1. Some suppliers create their own barcodes as a string of thirteen numbers to avoid paying the GS1 licence fees. Whilst this may have worked in the past, these numbers will now be rejected as invalid by marketplaces such as Amazon and eBay.

Incorrect matching

Details on marketplaces are frequently wrong or give a wrong quantity. This can be an issue when matching large catalogues by barcode were checking each listing is not practical.

What is an Amazon Repricing and how to use it? With BQool

In our second online seminar with BQool we look at repricing best practise. Repricing is the practise of dynamically changing prices to order to maximise Buy Box percentage. Sellers can alter prices manually but unless you have a very small number of product it is best to automate the process.

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  • Who should a merchant reprice against?
  • Should repricing consider a merchants feedback and fulfilment method?
  • Should shipping be taken into consideration I.e. Should the landed price be used?
  • What best practice does BQool recommend?

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