In Norway, there is no water fluoridation and little naturally occurring fluoride in drinking water. Fluoride toothpaste is used by 95% of the population and there is a long tradition of use of fluoride supplements. The purpose of this study was to analyse whether children who used fluoride toothpaste regularly and complied with the recommendations for use of fluoride supplements had less caries than other children at the age of 8 years. Most fluoride supplements sold in Norway are lozenge-type tablets, which allow for extended enamel exposure to fluoride. All children (n = 551) born in 1988 living in a suburban community in Norway were invited to participate. In those who participated (n = 470), caries was registered clinically and radiographically and parents provided data on use of supplements. Thirty-eight percent of the children had used fluoride supplements regularly during the period 0.5 to 4.0 years of age and 66% used supplements regularly at the age of 6 to 8 years. Multivariate analyses showed that the children complying with the recommendations for use of fluoride supplements during the period 0.5 to 4.0 years of age had lower caries experience (dmfs) and fewer decayed surfaces (ds) in primary teeth than other children. No significant associations were found between supplement use in childhood and caries prevalence (DMFS) or number of decayed surfaces (DS) in permanent teeth at the age of 8 years. Supplement use from 6 to 8 years of age was not associated with caries occurrence either in primary or in permanent teeth. Both mother's education and the quality of dental hygiene were inversely associated with caries occurrence.