Micro- and nanodimensional hard magnets are of high scientific and technological interest for data storage, micro- and nanoelectromechanical systems (MEMS/NEMS) as well as microfluidics. External nonmechanical forces, like the magnetic field gradient force, are promising to manipulate fluids or their containing species in microchannels [1,2]. The Fe-Pt alloy is a suitable system providing the required hard magnetic properties. To utilize micropatterned magnets for these applications and provide sufficient field gradients, carefully adjusted properties such as low residual stress, a homogeneous morphology and a certain thickness are required. Electrodeposition is a time and cost efficient method to deposit such microstructured magnets with complex geometries or high aspect ratios.     The electrochemical co-deposition of iron and platinum, however, is challenging due to their large difference in nobility and the high catalytic activity of the platinum. In previous studies, Fe-Pt films have been prepared using an uncomplexed FeSO4 - H2PtCl6 electrolyte. The deposition leads to an amorphous deposit containing up to 30 at. % oxygen [3,4]. A subsequent heat treatment is needed to reduce the oxygen content and get layers with good hard magnetic properties. A reduction of the oxygen content was also achieved by the deposition of multilayered films [5]. The low electrolyte stability reduces the long term usability and thus the reproducibility of the deposition. This deficiency avoids the deposition of thick films.   In this work we aim on the deposition of thick Fe-Pt films for microfluidic applications. We developed a stable electrolyte system by replacing FeSO4 with Fe2(SO4)3 thus avoiding the oxidation step from Fe2+ to Fe3+. By addition of 5-sulfosalicylic acid (SSA) a stable Fe3+ complex [6,7] is formed, expecting the prevention of iron hydroxide formation and its incorporation. Cyclic voltammetry in combination with electrochemical quartz crystal microbalance measurements have been used to get further insight into alloy deposition mechanisms. In order to identify the key parameters towards homogeneous and thick Fe50Pt50 films a systematic study of the electrolyte composition and deposition parameters has been performed. In the present contribution we discuss in particular the impact of deposition potential, potential regime, pulse time and electrolyte agitation. Fe50Pt50 films with ~1.6 µm thickness have been achieved (figure 1) by performing a potentiostatic deposition (E = -0.9 VSCE) using a rotating disk electrode (RDE).