Upselling involves offering a customer an additional product, accessory, or service related to their main purchase. This sales practice aims to enhance the initial offering, such as selling a tube of shoe polish with a pair of shoes or a tie with a shirt. It is generally suggested proactively by a salesperson in a store or automatically offered during an online purchase. Upselling is a common strategy for increasing the average order value while addressing the customer's additional needs.

The concept of upselling involves showcasing the different available variations of the same product. These variations may offer more options or higher quality. The main objective is to demonstrate to potential or existing customers the advantages they could gain by choosing an enhanced version compared to the base product. Generally, the focus is placed first on the base product to attract attention, then on the premium models to close a sale and generate higher revenue.

Upselling, or incentive selling, is a sales technique that encourages a customer to choose a more expensive or higher-quality product or service than the one they initially considered. This strategy aims to increase the average purchase amount by offering premium options, additional features, or complementary services. It can be implemented through direct or automated interactions, particularly on e-commerce platforms via recommendation systems. Upselling differs from cross-selling, which involves offering complementary products rather than upgrading existing ones.