A UK survey for the occurrence of aflatoxin M1in bulked dried milks (totalling 277 samples) obtained at monthly intervals from a number of commercial creameries in the UK over a two‐year period (1981–1983), showed 98% of the samples to have levels below 0.03 μg/kg. For liquid milks sampled from individual farms over the same period (totalling 409 samples), 94% of the samples had aflatoxin M1levels below 0.01 μg/kg. All samples were initially screened by a two‐dimensional thin layer chromatographic method and quantification of positive results was by reverse phase h.p.l.c. with fluorescence detection. The results of this survey show that UK milk is largely free of aflatoxin M1contamination, the incidence and levels, where observed, being significantly lower than for other European countries, which demonstrates the effectiveness of UK legislative action controlling feedstuff contamination.