Not many U23Bs still exist, but a few shortline and regional railroads still use them in everyday service. The Georgia Central Railway was one of the last U23B holdouts, rostering almost all of the remaining ex Southern Railway (U.S.) high short hood U23Bs. The Georgia Central as of July 2015 has all of its U23Bs off of the roster with the 3965 going to the Southern Appalachia Railway Museum in Oak Ridge, TN.
The Huntsville and Madison County Railroad Authority in Huntsville, AL, operates perhaps one of the last U23B's used in daily freight service, as of October 2015. HMCR 9554 was originally built in late 1974 as L&N 2800. The last U23B built, originally Conrail 2798, and more recently Providence and Worcester 2203, is in regular excursion service at the Naugatuck Railroad, operated by the Railroad Museum of New England in Thomaston, Connecticut.
CR 2798 was the last U23B built by GE in 1977, and the last Universal Series locomotive built for North American use. In this photo, it is leading a westbound train through Middlefield, Massachusetts, in June 1979.