Results of a 20 month split‐udder trial on the effect of discontinuation of postmilking teat disinfection on intramammary infections (IMI) with major and minor pathogens in seven dairy herds with a low somatic cell count are described. The incidence ofEscherichia coliIMI was found to be significantly lower, whereas the incidence of IMI withStaphylococcus aureusand minor pathogens was significantly higher in quarters for which postmilking teat disinfection was discontinued than in disinfected quarters. It was concluded that discontinuation of postmilking teat disinfection decreased the incidence ofE. coliIMI, accompanied by a, from a practical point of view, acceptable rise in somatic cell count. However, the possible increase in the incidence ofS. aureusIMI calls for careful monitoring of the dynamics of IMI with contagious pathogens, when postmilking teat disinfection is discontinued in an attempt to reduceE. colimastitis.