How to set/update duplicate SKUs in WooCommerce

Using duplicate SKUs (Stock Keeping Units) for products can be done for several reasons, though it’s generally advisable to avoid duplicate SKUs to maintain clarity and consistency in inventory management.

However, in certain scenarios, duplicate SKUs might be intentionally employed for specific purposes:

1. Differentiating Variants: If a product comes in multiple variations (e.g., different sizes, colors, or configurations), some businesses may assign the same base SKU to all variants and use additional identifiers to distinguish between them. While this may technically involve duplicate SKUs, it helps maintain a clear association between related products.
2. Multi-Channel Sales: Businesses selling products across multiple channels (e.g., online marketplaces, physical stores, and their own website) might use duplicate SKUs to sync inventory across these platforms. This can help prevent overselling and maintain accurate stock levels.
3. Merging Inventory Systems: In certain cases, businesses might merge or integrate different inventory systems. During this transition, they might temporarily use duplicate SKUs to reconcile and match products between the old and new systems.
4. Legacy Systems: Some businesses using legacy systems or dealing with data migration challenges may encounter instances where duplicate SKUs are unavoidable during the transition to a new system.

It’s important to note that while these reasons exist, the use of duplicate SKUs can lead to confusion, errors, and complications in inventory management. Whenever possible, it’s advisable to employ a unique SKU for each distinct product to maintain clarity and streamline inventory tracking processes. Modern inventory management systems often provide tools and features to handle product variations without resorting to duplicate SKUs.

WooCommerce out the box does not allow duplicate SKUs and as such, Setary does not either, but if you’ve the above and you still need to use duplicate SKUs you can do this with Setary.

Firstly, go to your theme within WordPress and open up functions.php, simply go to the bottom and add:

add_filter( 'wc_product_has_unique_sku', '__return_false' ); 

You should now be able to update SKUs to be duplicates.

There is one caveat with Setary, you will not be able to import products from CSV and merge data as Setary does not know which product to merge with as there will be multiple SKUs. SKUs will take priority over POST ID in this situation.