Traditional referral programs and newsletter capture programs give away coupon codes for the actions you do.
Example 1: Refer a friend and they get $10 and you get $10.
Example 2: Sign up for our newsletter and get a 10% coupon code
This is archaic. The user ends up having discount codes here there and everywhere and isn't able to track them. As a result, you get support tickets like "Where is my 10% coupon?" No one likes this.
This is why you should have one streamlined credit system that aligns with your loyalty program.
How it's done:
1) Make sure you select "Fixed amount of store credit" or "Amount of store credit based on how much they've spent" in the Referral Set up
2) Make sure you give store credit for newsletter/SMS sign up instead of codes.