New Zealand, along with the US and Australia, has one of the highest asthma rates among developed countries and previous analyses attribute this partly to insufficient home heating in certain neighborhoods. International public health and medical studies corroborate this link but strong evidence of causality is lacking. In this paper, we empirically investigate the effect of home heating on hospital asthma admissions using panel data techniques and controlling for endogeneity. The hypothesis that higher electricity prices (via less adequate heating) increase hospital asthma admissions is tested and receives strong empirical support across a number of model specifications and datasets used. (JEL Code: I12)