This paper evaluates the impact of water sector privatization in Colombia on access, price and water quality, as well as health outcomes using differences‐in‐differences methodology. The main findings of the impact of water privatization are: (i) an improvement in the quality of water and an increase in the frequency of the service in privatized urban municipalities for the lower quintiles; (ii) a positive effect on health outcomes in both urban and rural areas; (iii) a negative effect on payment for the lower quintiles; and (iv) strong negative effects on access to water in rural areas. Some of these effects appear in municipalities with better technical capacity.