The electrodeposition of the actinides U, Th, Pu, Am, and Cm on stainless steel disks was studied. A sodium hydrogen sulphate — sodium sulphate buffer 0.63M in total sulphate and a ratio sodium hydrogen sulphate to total sulphate ranging from 0.16 (pH 1.8) to 0.48 (pH 1.3) allows the quantitative electrodeposition of the given actinides. No actual pH measurement is needed. Moreover, sodium hydrogen sulphate is an excellent substrate for the wet ashing of organic matter prior to electrodeposition. The method is very robust.