Background: Studies have reported that one of the outcomes of on-going social and demographic transition is breakdown in families’ structure. Thus the emergence of single mother families is an observed trend which is associated with poverty and negative child outcome. This study examines the levels and factors associated with single motherhood in Southern Africa. Data source and methods: This is a cross-sectional study of Demographic and Health Survey (DHS) data sets for three Southern African countries of study: Lesotho (DHS) 2009, Swaziland (DHS) 2006-2007 and, Zimbabwe (DHS) 2010-2011. A total sample of 5586 women aged 15-49 for Zimbabwe, 4063 for Swaziland and 2541 for Lesotho who are either currently married or not and have at least one dependent child prior to the survey was included in the study. Data analysis was done at three stages; univariate, bivariate and multivariate level. Multivariate logistic regression which yielded odds ratio was used to identify the socioeconomic and demographic correlates of single motherhood. Results: The findings showed that the level of single motherhood in Zimbabwe is 20% (1091), Lesotho 25% (1011) and Swaziland 41% (1041) with premarital childbearing as the main source of single motherhood in the region, while widowhood and divorce is relatively low. Comparing the three countries of study in terms of correlates of single motherhood, the evidence suggested that age of respondents and number of living children, are correlates of single motherhood while religion was found not to be associated with single motherhood in all the countries of study. Younger women were more likely to become single mothers compared to older women while women with more than 2 living children are less likely to be single mothers compared to those with 1 or 2 living children. Conclusion: This study concludes that single motherhood is high in southern Africa. The implication of the rapid spread of single motherhood both reflects and reinforces the declining significance of marriage as a family status and a context for bearing and raising children. Also it may have negative implications for children from single mother families and the mothers themselves.