nonfamily

Nonfamily is a term used in sociology and demography to describe households or social units that do not consist of related family members. In statistical datasets, nonfamily households are those in which the householder is not related to all other residents. This includes households with a single occupant as well as those with two or more people who are not related by blood, marriage, or adoption.

In contrast, family households are composed of related individuals, typically including a householder and one or more relatives. The nonfamily designation therefore covers arrangements such as roommates, cohabiting partners who are not related, or groups of unrelated individuals living together. The distinction helps researchers analyze living arrangements, housing demand, and social structure separately from kin-based households.

Nonfamily patterns vary across countries and over time. In many developed nations, nonfamily households have grown due to factors such as aging populations, delayed or non-marriage, increased divorce rates, urbanization, and housing affordability. Cultural norms also influence the prevalence of nonfamily living arrangements, with some societies continuing to favor multi-generational or extended-family households.

Data definitions of nonfamily can differ by country and census, which can affect comparisons. Some classifications treat cohabiting partners who are not related as nonfamily, while others may use different criteria. Despite these variations, the nonfamily category generally serves to illuminate trends in independent living, shared housing, and the broader dynamics of household formation.