Referral links vs discount codes: how does each credit an affiliate?

Referral links and discount codes both tell a store which affiliate (a person or business that promotes the store) sent a customer, so that affiliate earns commission, the reward for a referred sale. A referral link, a web address with a tracking code that identifies the affiliate, is recorded when the customer opens it, before they shop. A discount code is recorded at checkout, the final step where the customer pays, and a standard code, one reusable code per affiliate, works even if the customer never clicked a link. Many affiliate programs offer both.

What you will learn

• How a referral link and a discount code each credit an affiliate
• The difference between standard and single-use discount codes
• What discount code leakage is and how to limit it

How a referral link credits an affiliate

When a customer opens an affiliate's referral link, the store can save a tracking cookie, a small file in the customer's browser that remembers which affiliate sent them. If the customer then completes an order from that browser, the order is credited to the affiliate. On a Shopify store, the store's customer privacy settings and the customer's cookie consent decide whether that cookie can be set.

Links suit online content such as videos, posts, and newsletters, where the audience can click, and they suit campaign tracking: seeing which promotion brought each visitor. Their limit is the cookie: a customer who declines cookies, switches devices, or clears cookies before buying may not be tracked.

How a discount code credits an affiliate

A discount code is a short word or code, such as SARAH10, that gives the customer a discount when they enter it at checkout. When the code belongs to one affiliate, entering it also tells the store who referred the customer. A standard code works entirely at checkout, so it does not depend on a cookie, and it works when a customer hears about the store in a podcast, in print, or in person. Single-use codes, described below, are the exception: a customer gets one only after opening the affiliate's referral link.

The trade-off is control. A link only credits the affiliate for customers who opened it, but a standard code can travel further than the audience it was meant for.

Standard and single-use discount codes

Standard codes

A standard code is reusable: the affiliate has one code, and anyone who enters it at checkout gets the discount and credits the affiliate. That suits codes meant to be public, such as a code printed on packaging or in a magazine, or a public offer.

Single-use codes

A single-use code works for one order only. In Simple Affiliate, a customer claims a unique code after opening the affiliate's referral link, and the code is applied at checkout. The name shown on the affiliate is the base for these codes: for a name such as SIMPLE, a claimed code looks like SIMPLE-XXXX. The name itself is only reserved, not a working discount code, so copying it does nothing.

Single-use codes tie the discount to the referral link: only customers who opened the affiliate's link can claim one. In Simple Affiliate they are available on the Pro plan and above, and not for discounts limited to certain countries or product variants (versions of a product, such as a size or color).

What is discount code leakage?

Discount code leakage happens when a code spreads beyond the audience it was meant for. It might be posted on a coupon site, a website that collects discount codes, or forwarded between friends. Anyone who finds a standard code gets the discount, and the affiliate earns commission, even if the shopper was already about to buy at full price. The store then gives away both a discount and a commission on a sale the affiliate did not bring in.

Standard codes can leak because they are reusable. A single-use code works once, and the reserved name does nothing on its own, so copies do not keep unlocking the discount. To see how leakage adds up, read the Simple Affiliate blog post on discount code leakage.

Choosing between links and codes

• Referral links: suit online content and campaign tracking, and credit only customers who opened the link.
• Standard codes: suit print, packaging, and public offers, where a reusable code is the point.
• Single-use codes: suit programs that want the discount to reach only customers the affiliate actually sent.

With Simple Affiliate, you choose whether affiliates use referral links, discount codes, or both. Discount codes are available on the Pro plan and above; see the Simple Affiliate pricing page for what each plan includes. Whatever you choose, tell affiliates and their customers how purchases are credited.

To switch a group of affiliates to one-time codes, read How to set up single-use discount codes (Pro plan) in the help center.