Despite the removal of user fees on public primary healthcare in Zambia, prior studies suggest that out-of-pocket payments are still significant. However, we have little understanding of the extent to which out-of-pocket payments lead patients to hardship methods of financing out-of-pocket costs. This study analyses the prevalence and determinants of hardship financing arising from out-of-pocket payments in healthcare, using data from a nationally-representative household health expenditure survey conducted in 2014. We employ a sequential logistic regression model to examine the factors associated with the risk of hardship financing conditional on reporting an illness and an out-of-pocket expenditure. The results show that up to 11% of households who reported an illness had borrowed money, or sold items or asked a friend for help, or displaced other household consumption in order to pay for health care. The risk of hardship financing was higher among the poorest households, female headed-households and households who reside further from health facilities. Improvements in physical access and quality of public health services have the potential to reduce the incidence of hardship financing especially among the poorest.