This study assessed whether agricultural and household incomes were the same across different agro-ecological environments in Bangladesh. An in-depth analysis of the effect of unfavourable ecologies on maternal and child malnutrition was carried out. Data were from a longitudinal data set comprising a nationally representative data sample collected in 2014 and the Food Security Nutrition Surveillance Project (FSNSP) conducted in 2011 and 2012. Anthropometric indices were used to assess the nutritional status of mothers and under-five children. The key variables of interest were food seasonality and geographical location. Data were analysed using the General Linear Model and multinomial and binary logistic regression analysis. Panel data analysis showed that household income was not equal across agro-ecological zones, indicating that the fragility of the environment affects a household’s ability to access food, and thus the nutritional status of mothers and children. Coastal areas of Bangladesh were found to be less dependent on agriculture, particularly cultivation, which had diminished during last few decades. Per capita income has been increasing in coastal areas of Bangladesh, led by remittance (money sent home by migrant workers) growing at 8% per year against 6% in other areas. Regression analysis showed that a household in a coastal zone earned 19% less than one in more favourable zones. Although the income from farm practices was found to be lower in unfavourable areas, the deficiency was compensated by increased non-farm incomes. The results from the FSNSP data showed that overall the rates of stunting and wasting among under-five children were 37% and 11.7%, respectively, and nearly 28% of mothers suffered from undernutrition. A highly significant regional heterogeneity in undernutrition was found, with alarmingly high levels in the Haor Basin and coastal belt areas. There were significantly higher rates of underweight and wasting in the monsoon season compared with the two harvest seasons among children under the age of five. The findings stress the importance of bringing geographical location and seasonality thinking into debates on hunger and nutrition in Bangladesh.