Online grocery customers are a new and rapidly growing market segment that calls for new marketing strategies and exploration of their profile. This study compares the shopping behaviour of exclusive online and brick-and-mortar customers by analyzing their transaction history and loyalty program records. Factor analysis was performed to reveal the main dimensions that explain customers’ behavior and clustering methods were used to identify the major customer profiles. The research uncovered differences in the purchase frequency, transaction amounts, and preferred product categories. The most important customer profiles of both categories were studied and valuable insights were derived about their needs and preferences.