Abstract The structural relaxation of ferromagnetic glasses containing about 20at.% metalloid has been studied by using differential scanning calorimetry to measure the Curie temperature (T c). The kinetics of the T c changes on annealing are shown to depend not only on the annealing temperature, but also on the direction of the change: the change in T c is slower in a structure with a lower fictive temperature. A series of isochronal anneals on FeB, FeNiB, FePB and FeNiPB glasses suggests that, whilst the addition of a second transition metal roughly doubles the rise of T c on annealing at a given T/T x, the metalloids broaden and shift to lower T/T x the temperature range over which relaxation occurs. Care has to be exercised in interpreting the T c changes, since they may be due, not only to structural relaxation, but also to primary crystallisation and phase separation: anomalous results are obtained from FeMoB and FePB glasses. In a FeB glass cold-rolling appears to have no effect on the T c changes induced by subsequent annealing. Interpretations of the T c changes are considered both in terms of specific mechanisms and in terms of glass relaxation in general.