Background: The rapid development of e-commerce has led to significant changes in last-mile logistics, where innovative delivery solutions such as parcel lockers are increasingly considered to improve efficiency and flexibility. Methods: This study analyzes user attitudes and behavior toward traditional delivery and parcel locker usage through a quantitative survey conducted in November 2024 in Serbia, on a sample of 420 respondents with diverse demographic characteristics. Results: The findings indicate that, despite recognized advantages such as flexibility, accessibility, and reduced risk of missed deliveries, parcel lockers remain underutilized. This is mainly due to limited user awareness, insufficient infrastructure, and a strong preference for traditional home delivery. Statistically significant differences were identified across demographic groups, including gender, age, education level, occupation, and place of residence. Conclusions: The results suggest that improving infrastructure, increasing user awareness, and implementing targeted communication strategies could significantly enhance the adoption of parcel lockers. The study contributes to a better understanding of user behavior and supports the development of more efficient and user-oriented last-mile delivery solutions.