This study examined the application of promotional techniques on library routine services in university libraries in Edo and Delta States, Nigeria. The study adopted a descriptive research design. The population of study was 257 comprising librarians and library officers from university libraries in the Edo and Delta states. Census sampling technique was adopted to utilize the entire population. Data were collected using a structured questionnaire which were analysed using descriptive statistics and Pearson’s Product-Moment Correlation Coefficient. Findings revealed that both traditional and digital promotional techniques were used. Core library services like reference, lending, and user education were both widely offered and promoted, while services such as translation and interlibrary loans were under-promoted. A significant positive relationship was found between the use of promotional techniques and the level of routine service utilization. The study concluded that promotional efforts directly impact library service delivery. It recommends that library management adopt structured and technology-integrated promotional strategies, and that institutions support these initiatives with adequate funding and training.