Introduction: Breastfeeding decreases morbidity, mortality and promotes health in the mother and child. The lower morbidity in relative terms in breastfed versus non-breastfed infants reduces healthcare costs. In Colombia, the duration of breastfeeding is far from desirable times and continues to decline. Objectives: The objectives were (a) to determine economic inequality based on monetary poverty at the ecological level in the duration of exclusive breastfeeding (EBF) and total breastfeeding (BF) and (b) to establish the social determinants of EBF and BF using the territory as a unit of analysis. Method: An ecological study was conducted based on data collected regarding the median duration of exclusive breastfeeding and total breastfeeding. The information was provided by 9,389 mothers with children less than 36 months who responded to the National Survey of the Nutritional Situation of 2010 in Colombia. The data were summarized in 24 departments or geodemographic units that represent the Colombian territory (n=24). Fourteen variables representing the economic, social, human and structural development levels in the territory were related by linear regression to explain the duration of EBF and BF. Results: EBF lasted 1.18 months (95% CI: 1.00 to 1.36), and BF lasted 14.79 months (95% CI: 13.50 to 16.08). Economic inequality was low, and the Gini coefficient was 0.35 for EBF and 0.10 for BF. The EBF duration is affected by the gender empowerment measure (GEM) (β=-1.94, p=0.006) and medical coverage (%) (β=-0.02, p=0.060). The BF duration is explained by the Monetary poverty (β=0.12, p=0.007) GEM (β=-9.94, p=0.033) and Female abuse rate x 100,000 (β=0.01, p=0.005). Conclusions: The impact of social and human development is greater than the economic aspect as a determinant of EBF and BF duration in Colombia. Exclusive and total breastfeeding are phenomena explained differently.