A unique promo code (also referred to as bulk code) is a single promo code generated as a part of a larger promo campaign. Unlike standalone promo codes, unique codes can be published (assigned) to individual customers. Moreover, unique codes usually carry rigid redemptions limits (e.g., once per customer) to secure the campaign budget and prevent fraud. When to use unique promo codes?Unique promo codes work best for campaigns with predefined targeting rules, e.g., specific segment-only. They require more technical know-how and deeper integration to implement than standalone codes, but they also tend to perform better than open-for-all standalone coupon codes. They are also easier to track as attribution and redemption can be tracked individually and on a case-per-case basis. Go here to learn how to build a campaign of unique promo codes.