How sad is it that all of our new trains and rolling stock is imported from other countries? We used to be world leaders in locomotive and train design yet there isn't a single UK owned mainline locomotive/train manufacturer left.
According to Gemini AI:
The most recent rail locomotive built in the UK is a steam locomotive named 6880 "Betton Grange," which was completed in 2023. It's a new build of a Great Western Railway (GWR) design from the 1930s.
Kind of ironic
But when diesel or electric is specified:
If you're referring to a conventional, stand-alone diesel or electric locomotive, the last one built in the UK was a Class 60 diesel-electric locomotive, manufactured by Brush Traction in Loughborough. The final locomotive of this class was built in 1993.
However, if you include electric multiple units (EMUs) and diesel multiple units (DMUs), which are self-propelled passenger trains, the timeline is much more recent. The UK still has a number of active rail vehicle factories. Companies like Alstom, which has a factory in Derby, continue to produce new trains for the UK rail network. These modern units are often designed as integrated trainsets rather than separate locomotives.
Therefore, while the Class 60 was the last of its kind in the traditional sense of a "locomotive," the last traction units built in the UK were far more recent and continue to be produced today.