Abstract: In a process of phosphatizing metal surfaces, which at least partly consist of iron or steel, in accordance with the low-zinc technology, the metal surfaces are brought in contact with aqueous acid phosphatizing solutions at a temperature of 30 to 65° C. for a period of 1 to 8 min, which solutions contain 0.4 to 2.0 g/l Zn 7 to 25 g/l P2O5 0.005 to 0.5 g/l peroxide (calc. as H2O2) 0.01 to 10 g/l formate (calc. as formate ion), are free from chlorate and added nitrite, and in which the weight ratio of free P2O5 to total P2O5 has been adjusted to a value in the range from 0.03 to 0.20, and the content of free acid has been adjusted to a value in the range from 0.5 to 2.5. After contact with the phosphatizing solution, the workpiece is rerinsed with water, which has been adjusted with mineral acid to a pH of from 3.6 to 5.0.