The geographical diversity of African cities creates context-specific strengths and weaknesses in household food security that come to light in the comparative case study presented in this paper. A recent survey of low-income households in 11 southern African cities found a much higher rate of food security in Blantyre (48%) relative to Gaborone (18%), which was a surprising finding considering Blantyre’s lower ‘development’ status in terms of urban infrastructure, economic opportunities and urban planning. A comparison of the relative scales at which the food production and distribution networks operate to feed each of the cities offers some insight into why Gaborone’s ‘development’ is paradoxically linked to the higher level in food insecurity among its low-income households. The majority of households in the Blantyre survey produced some of their own food and usually purchased food from informal markets; by contrast, most of the food in Gaborone is produced outside of the country and accessed through international supermarket chains. The comparison of these cities, typical of the urban extremes in southern Africa, throws into bold relief the importance of scale for theorizing urban food security in the Global South.