Background <p>Complementary feeding represents a critical milestone in infant nutrition, where appropriate timing and informed decision-making are of great importance. Maternal factors such as education level, socioeconomic status, cultural values, and access to information sources play a significant role in shaping complementary feeding practices.</p> Methods <p>This cross-sectional study was conducted with 504 mothers at the Pediatric Outpatient Clinic of Ankara Bilkent City Hospital between February and April 2025. Data were collected through a structured questionnaire that included mothers’ sociodemographic characteristics, complementary feeding practices, and sources of information. Statistical analyses were performed to examine the associations between maternal characteristics and feeding behaviors.</p> Results <p>A total of 40.2% of the mothers reported initiating complementary feeding at the 5th month, while 39.0% started at the 6th month. Complementary feeding behaviors were significantly influenced by various sociodemographic factors such as maternal education level, employment status, and family support (<i>p</i> &lt; 0.001). Mothers with lower levels of education and income were more likely to start earlier, whereas employed mothers tended to follow the recommended guidelines more closely. Differences in the timing of complementary feeding were also observed between mothers with and without family support.</p> Conclusions <p>Maternal sociodemographic characteristics, cultural factors, and perceptions of workload significantly influence complementary feeding behaviors. Developing public health interventions that are sensitive to the sociocultural context—particularly for at-risk groups—is essential to promote appropriate infant feeding practices.</p>