This study sharpens comparisons of gender differences in poverty in South Africa by distinguishing households according to the gender composition of resident adults rather than by household headship. The categories of female-dominated and male-dominated households (where all adults are either women or men respectively) are subsets of female- and male-headed households but their classification avoids many of the problems associated with the concept of household headship. Using nationally representative micro-data, we show that both female-dominated and male-dominated households have become more prevalent over time. Comparing these household types reveals that when men live without women, they mostly live alone; while women who live without men are far more likely to live with children. These differences in household composition help to explain why the gender poverty differential is more marked when comparing female- and male-dominated households as opposed to the broader and more heterogeneous categories of female- and male-headed households.