We will show how magnetic field-enhanced unidirectional ice-templating can be used to fabricate hybrid magnetic foams out of tannic acid-coated iron oxide nanoparticles (TA@IONP) and TEMPO-oxidized cellulose nanofibrils (TOCNF). These anisotropic foams have a high IONP content of up to 87 wt% and a saturation magnetization of 83.2 emu.g^-1.