Well, the title of the article itself explains the discount scenario. So let's get into an example configuration right away

Let's create a new Price Rule 

General Tab

Choose the Quantity based / BOGO deals method.

Conditions tab

I have chosen to apply for All Products in the store. You can also choose it to apply only when products from Specific categories are bought. See the FAQ for a few variations in the discount scenario.

NOTE: Make sure you check the box to count the quantities cumulatively.

Discount tab:

Choose the adjustment type as "Product Discount" and apply it for "Any one cheapest item from All"

Heads up! Notice that i have set the minimum quantity as 2. That is important as you want the discount on the cheapest item in the cart. That means there should be at least 2 products in the cart or at least 2 quantities on the same item.

Also notice that i chose to use Limited percent and set it to 50%.
You can even even set to to 100% to give the cheapest item free.

Frequently Asked Questions

1. How to set up "Buy any product from selected categories and get 50% off on the cheapest item from those categories"

Simple. In the conditions tab, choose to apply the rule for Specific Categories.

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