You can send invoices automatically as soon as you fulfill an order by following the simple steps below.
Your customers will receive an invoice as soon as you fulfill your order. If you activate this option, you can send separate invoice emails to your customers.
Step 1: Open Simple Invoice from the “Apps” section of your Shopify store.
Step 2: Click on “Settings” on the Simple Invoice dashboard.
Step 3: Scroll down to the Sending Invoices with Simple Invoice section, and click on the Auto on fulfillment option.
Step 4: Click on the Save button.