How do Shopify discount codes work with bundle discounts?

Bundle discounts added through Simple Bundles works independently of Shopify's discount codes. This means that your customers can get a discount on a bundle as well as use a discount code at checkout.

Creating a bundle discount 

When you're creating your bundle, you'll see your Bundle value, which is the sum of all the bundle items, and the Price that you'll price your bundle at. In this example, I've priced my bundle at $60 which equates to a discount of 23.8%. To my customers, the $60 will appear as the bundle's regular price. 

I can also check Update bundle compare at price in Shopify to bundle value. My customers would then see the bundle's compare at price (regular price) and discount price. The compare at price appears differently depending on the Shopify theme that you're using.