Background: Early initiation of breastfeeding within the first hour of birth and exclusive breastfeeding (EBF) for the first six months of life are beneficial for child survival and long-term health. Yet breastfeeding rates remain sub-optimal in Northwestern Nigeria, and such practices are often influenced by complex psychosocial factors at cognitive, social and emotional levels. To understand these influences, we developed a set of breastfeeding-related ideational factors and quantitatively examined their relationship with early initiation of breastfeeding and EBF practices., Methods: A cross-sectional population-based survey was conducted in Kebbi, Sokoto, and Zamfara states from September-October 2019. A random sample of 3039 women with a child under-2 years was obtained. Respondents were asked about the two main outcomes, early initiation of breastfeeding and EBF, as well as breastfeeding-related ideations according to the Ideation Model of Strategic Communication and Behavior Change. Average marginal effects were estimated from mixed-effects logistic regression models adjusted for ideational and socio-demographic variables., Results: Among 3039 women with a child under 2 years of age, 42.1% (95% CI 35.1%, 49.4%) practiced early initiation of breastfeeding, while 37.5% (95% CI 29.8%, 46.0%) out of 721 infants aged 0-5 months were exclusively breastfed. Women who knew early initiation of breastfeeding was protective of newborn health had 7.9 percentage points (pp) [95% CI 3.9, 11.9] higher likelihood of early initiation of breastfeeding practice than those who did not know. Women who believed colostrum was harmful had 8.4 pp lower likelihood of early initiation of breastfeeding (95% CI -12.4, -4.3) and EBF (95% CI -15.7%, -1.0%) than those without that belief. We found higher likelihood of early initiation of breastfeeding (5.1 pp, 95% CI 0.8%, 9.4%) and EBF (13.3 pp, 95% CI 5.0%, 22.0%) among women who knew at least one benefit of breastfeeding compared to those who did not know. Knowing the timing for introducing complementary foods andself-efficacy to practice EBF were also significantly associated with EBF practices., Conclusion: Ideational metrics provide significant insights for SBC programs aiming to change and improve health behaviors, including breastfeeding practices, Various cognitive, emotional and social domains played a significant role in women's breastfeeding decisions. Maternal knowledge about the benefits of breastfeeding to the mother (cognitive), knowledge of the appropriate time to introduce complementary foods (cognitive), beliefs on colostrum (cognitive), self-efficacy to breastfeed (emotional) and perceived social norms (social) are among the most important ideations for SBC programs to target to increase early initiation of breastfeeding and EBF rates in northwestern Nigeria., (© 2022. The Author(s).)