To quantify the extent of time spent by family and friends caring for drinkers and their dependents, to estimate the cost of this time and to measure which factors predict time spent caring.Data are from a nationwide Alcohol's Harm to Others Survey of 2649 Australians, in which 778 respondents reported they were harmed by a known drinker. Time spent on four caring activities was self-reported by these respondents and tallied to estimate how many hours they spent caring for the drinker, the drinker's children or other dependents. Bivariate and multivariate linear regression models were employed to examine factors predicting time spent caring.Respondents who reported they were harmed by a drinker they knew had spent on average 32 h caring for this drinker and their dependents in the past 12 months. Applying these figures to the Australian population, but discounting by 90% because this time may be seen be a voluntary demonstration of connection, an annual cost of caring in 2008 would amount to AU$250 million. A significant positive association was found between time spent caring and the drinking level and drinking frequency of the heavy drinking other person.Caring for drinking family members, friends, co-workers and a drinker's dependents can be a substantial burden. Policy approaches that reduce population drinking and individual risky drinking levels are potential means to reduce the burden of caring due to others' drinking.