The magnetic structures of CeBi have been examined as a function of field with neutron diffraction. At low fields unusual domain reorientation effects are observed. For H≳18 kOe a 3+, 1‐ spin configuration is found. A first‐order transition to induced ferro‐magnetic behavior occurs at 47.5 kOe. X‐ray experiments at low temperature show that no lattice distortion occurs at either TN=25 K or the I‐IA transition at 12.5 K. A volume discontinuity is observed at the low temperature transition.