The paper explains how customers make a purchase decision. The consumer decision process in an offline environment is carried out through five main phases, which include need recognition, information search, evaluation of alternative possibilities, purchase, and post-purchase behavior. In an online environment, the process is the same, but the phase of searching for information about a product or service is different from the tradi-tional searching for information. Customer behavior can be influenced by various envi-ronments such as economic, cultural, and social. Customers can be segmented using both demographic, geographic, psychographic, and behavioral variables in both offline and online environments. A survey was conducted on the customer behavior of cosmetic products. Research has shown that most consumers most often shop in physical specialty stores such as DM and BIPA. They make the purchase once or three times a month, and for the purchase they set aside between 50 and 300 kuna. Consumers most often buy body, face and hand care products, and the purchase decision is most influenced by price, quality, appear-ance, and packaging design.