By default, there isn't a good way to add discount codes to draft orders in Shopify.
If you read the official documentation, it says:
Discount codes can't be applied at checkout for orders created as draft order invoices.
However, there is a workaround that you can do.
Let's create a simple discount code - for example 15% off your entire order with a minimum purchase price of $100.
In this example, I use EDDY15OFF and create a code for it. Here's how it looks in my Shopify:
You can now go to Orders > Create Order and then click "Add Discount".
Here you will type in the exact same discount and the same code in the Reason field.
Now if you want to send this Draft order via email, simply leave a note to your customer.
Here's your invoice with your coupon code EDDY15OFF already applied. If you add any additional items, be sure to just re-apply your code.
The email invoice will look like this:
And inside the checkout, the order summary will look like this:
It's not a perfect fix, it won't work for discount codes that only apply to specific products, collections or customers.
The discount code also won't receive the sale in your "Sales by discount report". But this workaround will be fine for the simple cases.
If you're looking for a checkout app that allows for discount codes to be used in Draft orders, I'm working on one - sign up to my newsletter below to get updated.
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