This European standard specifies a method for the determination of total and water extractable boron in mineral fertilizers containing less than or equal to 10 % boron. The method is not suitable for fertilizers with Fe concentrations more than twenty times higher than the concentration of boron. The extraction methods are specified in prEN 16962 and/or prEN 16964. The method can also be used for the determination of boron in mineral fertilizers containing more than 10 % boron after appropriate dilution of the extracts.