Abstract The effects of Co, Zr, Nb, Ga and Dy additions upon the magnetic properties of PrFeB-based alloys have been studied. Bonded magnets have been prepared from as-cast and homogenised alloys using an optimised hydrogenation disproportionation desorption and recombination (HDDR) process. In general, the HDDR bonded magnets from homogenised alloys exhibited higher remanence ( B r), squareness factor (SF) and intrinsic coercivity ( i H c). In particular, the Pr 13.7Fe 63.5Co 16.7B 6Nb 0.1 HDDR magnet exhibited the best overall magnetic properties ( B r=1032±20 mT, i H c=793±20 kA/m and SF=0.51), indicating that Co and Nb additions, in these proportions have a beneficial effect on PrFeB-based magnets. Conversely, additions of Ga and Dy were observed to dramatically reduce the intrinsic coercivity of Pr-based HDDR magnets.