The first seven trains, originally consisting of two cars, entered service on 8 May 1978 in the Bilbao-San Sebastián line.

[5] Already in 1978, fifteen intermediate cars were ordered for the trains in service in the Basque Country.

[2] Only the first eight cars were delivered before the narrow-gauge railways were transferred to the Basque Government, while the other seven were built in 1980.

The Euskotren units had their interiors reformed in the 1990s and were substantially modernized in the early 2000s.

The trains in service in the Basque Country had a third non-powered car added shortly after their introduction.