The first electric locomotives to be procured in large numbers in post-war Belgium were the later HLE 22, 23 and 25. These were four-axle locomotives with a top speed of 130 km/h, an hourly output of 1,880 kW and a continuous output of 1,740 kW. The original version was the type 122, of which 50 examples were built between 1953 and 1954. Initially, they were only designed for 3,000 volts direct current and had ventilation grilles in the roof area, which later turned out to be problematic with regard to the ingress of rain. They were designated as Series 22 in the new numbering scheme of 1971.
Due to the problems with the arrangement of the ventilation grilles, the type 123 was built between 1955 and 1957, in which the grilles were arranged in the lower area of the side walls. Since these locomotives were also intended to pull heavier freight trains, the weight was increased by five tonnes. After 83 examples of the 123, further examples were built in 1960 and 1961, which were again three tonnes lighter than the type 122. These were 16 of the type 125 and six of the type 140. The latter were distinguished by the fact that they were designed for 140 km/h with another gear ratio. Since the ten additional km/h did not pay off considering the loss of tractive power, this was converted to 130 km/h and classified as type 125. From 1971 the types 123 and 125 became the HLE 23 and 25.
In 1971, an HLE 23 locomotive was fitted with a streamlined paneling on one side and was operated at up to 200 km/h in test runs. Other HLE 23 locomotives were later equipped for multiple working and were then often found in pairs in front of freight trains. Eight examples of the HLE 25 were equipped in the 1970s as the first Belgian locomotives for push-pull operation with one locomotive at each end of the train. They were designated HLE 25.5. Later, further HLE 25 were equipped for push-pull operation and passenger coaches with luggage compartments were rebuilt into driving trailers.
The HLE25.5 were also equipped for operation in the Netherlands and could be operated at full power under 1,500 volts. Twelve HLE 22 were also converted for operation in the Netherlands, but could only run at lower power there. In the 21st century, the locomotives were mostly only used for freight trains. In 2009, most examples were still in service but then faced rapid retirement and the last examples of the 25.5 disappeared in 2012.