One of the questions that I get asked most about Magento SEO is how the relationship between a configurable product and simple variants of that product should be managed from an SEO perspective – so I decided to write a blog post about it.
Configurable products are used in Magento to allow merchants to offer users configuration options for the products in their catalog, such as colour, size, design or any other variable. This type of product is used by most Magento merchants because they help to provide a good, clean user experience and they’re easy to manage.
The problem arises when a merchant decides to use a configurable product as well as simple variants for a single product. This most commonly happens because the retailer wants to display the simple variants via product list pages (so they can merchandise better or make it easier for the user to reach the pre-defined version) or they want the different versions for PLA / Google Shopping or other paid advertising channels.
If you’re doing this, it’s important to ensure that the canonical tag used on each of the simple products points back to the primary configurable version – to prevent duplicate variants of the product from being indexed by Google and other search engines.
I’d suggest that you either use a plugin (or build the functionality) to allow you to set page-level canonical tags (which would be quite tricky to manage) or try and create a canonical logic based on the product SKU (which is what I’ve seen merchants do in the past). Even if you’re adding unique identifiers to the product SKU (appending 01 for size for example), you should still be able to set the canonical logic based on that. This isn’t an easy fix, however it’s something I’d definitely suggest doing to avoid both cannobolisation and over-indexation issues.