With ongoing climate change, food insecurity is likely to become more widespread in most small-holder and subsistence farm households in sub-Saharan Africa. However, the existence and extent of gendered food (in)security remains unclear. This study extends existing knowledge by assessing gender inequality in food (in)security amongst small-holder farm households in urban and rural areas of South Africa. To do so, we use the gender of the head of household in a treatment effects framework. Our results show that male-headed farm households are more food secure compared to female-headed households, with the latter depending more on agriculture. We further observe that chronic food insecurity is greater and the gender gap in food security is wider amongst rural than urban households. Our results suggest that the current policy interest in promoting both rural and urban agriculture is likely to increase food security in both male- and female-headed households, and to reduce the gender gap.