Indigenous village chickens (IVCs) significantly contribute to rural development. There is considerable variation in family flock size and age-sex structure of IVCs. This study reports the family flock size, age-sex group structure, and demographic history of IVCs. This work involved a cross-sectional study conducted using face-to-face general informants' individual interviews with 119 smallholder farmers in highland and lowland agroecological zones. The average family flock size of the sampled households was small (mean = 7.28, range: 1-38). Female birds (hens and pullets) represented the largest proportion of the family flocks (50.2%). The proportion of chicks (26.4%) and pullets (14.4%) was lower than that of hens (35.8%), which creates a considerable challenge in producing replacement breeding flocks. Similarly, the proportion of cockerels (9.1%) was lower than that of cocks (14.3%). The average cock-to-hen ratio (one cock to seven hens) was better than the commonly recommended proportion (1 cock to 8-10 hens). As a result, smallholder farmers have not faced the problem of producing infertile eggs. The estimated effective population size (Ne) of 4.02 and the corresponding inbreeding coefficient of 0.12 at the family flock level show that to some extent inbreeding may occur at the family flock level; besides, the estimated Ne represents 55.2% of the census size. However, inbreeding could be offset by the high rate of flock turnover and uncontrolled mating among scavenging birds. Family flocks contain a few birds, which may lead to consanguineous mating. Inbreeding is, however, considerably reduced by uncontrolled breeding among birds that share a common scavenging ground. The driving factors behind the low proportion of chicks and juvenile birds and the family flock size need to be further investigated to improve the contribution of local chickens to rural livelihoods.