<p>Housing insecurity is a key social determinant of a wide range of health outcomes, subject to large racial inequities, and with a likely sensitive period in childhood. Housing insecurity can manifest in multiple ways and change over time, but previous studies have primarily focused on single dimensions or a single time point. This study examines cumulative exposure to multiple forms of housing insecurity from birth to adolescence, overall, and by race in large US cities. Using data from the Future of Families and Child Wellbeing Study (FFCWS), we estimated cumulative incidence and mean cumulative count of several forms of housing insecurity, accounting for missing data (due primarily to gaps between waves) using lower bounds and a mixed modeling approach. Between 45% (lower bound) and 71% (modeled) of children experienced at least one housing insecurity event by age 15. The average number of events among children who had any event was between 2.63 (lower bound) and 6.11 (modeled). Children of non-Hispanic Black and Hispanic mothers, compared to non-Hispanic White mothers, were more likely to experience an initial event, but once experienced, had similar numbers of events. We find a massive and cyclical burden of housing insecurity during childhood. Large racial differences in incidence of first events, but not repeated events, suggest that preventive interventions would most effectively mitigate racial inequities in housing insecurity.</p>