Food insecurity has multiple negative effects on maternal and child health and nutritional outcomes. There is a dearth of up-to-date evidence on the prevalence of food insecurity in Bangladesh based on geographical variations. We investigated the prevalence of food insecurity based on geographical variations and its associated factors. We pooled data from seven cross-sectional surveys conducted in 15,009 households from March 2015 to May 2018. This study was a part of the evaluation of the Maternal Infant Young Child Nutrition Phase 2 programme implemented by BRAC, one of the largest international non-governmental organizations located in Bangladesh that covered rural areas in 26 districts and two urban slums in Dhaka, Bangladesh. We used Household Food Insecurity Access Scale (a widely used scale to measure household food insecurity) to estimate the food insecurity status from the data collected through a face-to-face interview using a structured questionnaire. Hot spot analysis was conducted using the Getis-Ord Gi* statistic. The multiple logistic regression model was applied to explore the associated factors of food insecurity. The food insecurity hotspots were in the northwestern, central-southwestern, and coastal districts of Bangladesh. The overall prevalence of mild, moderate, and severe food insecurity were 12.7%, 13.8%, and 3.5%, respectively. In the adjusted model, household heads and caregivers of children with five or more years of schooling had respectively 42% (adjusted odds ratio (AOR): 0.58, 95% confidence interval (CI): 0.52, 0.64) and 46% (AOR: 0.54; 95% CI: 0.49, 0.61) less likelihood to suffer from food insecurity. Households in the middle (AOR: 0.58, 95% CI: 0.52, 0.65) and rich (AOR: 0.32, 95% CI: 0.28, 0.36) wealth status had lower odds of food insecurity. Food insecurity is widely spread in rural districts of Bangladesh and the degree of vulnerability is higher among the households of the northwestern, central-southwestern, and coastal areas of Bangladesh. Comprehensive interventions including strategies for poverty reduction and education for all might be effective to reduce food insecurity at rural households in Bangladesh.