Background: Early initiation of breastfeeding (EIBF) within the first hour of birth reduces neonatal morbidity and mortality and supports successful lactation. Despite high institutional delivery rates, EIBF remains sub-optimal in many settings. This study assessed the mean breastfeeding initiation time and the maternal, obstetric and socio-demographic factors influencing it in a tertiary care hospital. Methods: A hospital-based, descriptive cross-sectional study was conducted in the maternity wards of Nazareth Hospital, Shillong, from 1 July 2022 to 30 June 2023. All live newborns delivered at the hospital whose mothers gave informed consent were enrolled by consecutive sampling (N = 471). Initiation time and 18 study variables were recorded on a structured proforma. Chi-square test, independent-samples t-test and one-way ANOVA were applied; p < 0.05 was considered significant. Results: The mean initiation time was 118.3 minutes (median 125; IQR 50–164), nearly double the WHO-recommended 60 minutes. Only 27.4% (n = 129) of neonates were breastfed within the first hour, below the national (41.8%) and state (78.8%) NFHS-5 averages. Mode of delivery was the strongest determinant: EIBF occurred in 79.4% of vaginal deliveries versus 0.9% of cesarean sections (p < 0.001), with mean times of 45.79 versus 154.90 minutes (p < 0.0001). Birth order (p = 0.026), maternal occupation (p < 0.0001) and religion (p = 0.015) were also significantly associated with initiation time, whereas maternal age, education, socioeconomic status and prior breastfeeding knowledge were not. Conclusion: Breastfeeding initiation was substantially delayed, driven largely by a high cesarean rate and absence of intra-operative breastfeeding support. Targeted interventions for cesarean deliveries, quality antenatal counselling and baby-friendly institutional practices are needed to align local practice with WHO guidelines.