Electroplating is compatible with the deposition of relatively thick layers i.e. several µm to 10s- of µm. However eddy current losses mean that thick layers will have an inferior frequency response. We have used a low content phosphorous bath together with pulse reverse plating to generate Co-rich and Co-deficient multi-nanolayers of CoP having improved saturation magnetisation and a better frequency response. The plating parameters have been optimised in order to produce a material with low loss, and a high permeability of around 700 retained up to 103 MHz for a sample with a thickness of 1.7 µm and a resistivity of 136 µO cm. © 2008 Elsevier B.V. All rights reserved.