Multiple Promotions on an Order
While multiple discounts can apply to the same order they are not cumulative and only the best discount will be applied to each line item. The exception is vouchers. If two vouchers of $20 each are applied to an order then they will accumulate and $40 will be taken off the total price.

To illustrate how multiple discounts are applied, imagine that you have special prices on some of your products across the site as follows:



In the above cart you can see the Pyramid t-shirt has a $4.95 discount which is roughly a 16% discount, whilst the Sphere t-shirt has $9.95 off, which is roughly a 33% discount, and the Sphere t-shirt has no price special at all. Now let's see what happens when we apply 20% discount across the site. 



We see that the 20% discount has applied to the Cube and Pyramid t-shirts but not to the Sphere t-shirt. This is because the special price already applied to the pyramid t-shirt is greater than the discount applied across the site. The site will automatically apply the largest discount to a product. 

The same goes for shipping discounts. When multiple shipping discounts apply to a cart, Storbie will apply the one that gives the customer the biggest shipping discount. As only the greatest shipping discount applies, you can create multiple shipping discounts that get better as the customer adds more products to their cart.  
Example - Create tiered shipping discounts
As only the greatest shipping discount applies, you can create multiple shipping discounts that get better as the customer adds more products to their cart. 

1. Choose that you want to add a Cart Discount that discounts shipping prices if certain criteria are met. 
2. Enter a name and leave the purchase dates blank.
3. On the criteria step, enter that the customer must spend at least $100 
4. Choose to give 50% off shipping to a particular region, click finish
5. Add another shipping discount. This time make the criteria $200.
6. Choose to give 80% off shipping, click FINISH. 
7. Create an order which totals more than $100 and less than $200. The 50% discount will apply. 
   
8. Add more products to the order so that it now has $200 or more.  The 80% discount will now apply as the 50% discount has been bettered.