The Millennium Time was taking sightseers from Westminster to the Tower of London when it was involved in a crash near Blackfriars.
Paramedics treated six people for minor injuries including neck and knee pains as well as shock. The bow of the Millennium Time, operated by City Cruises, was badly mangled. Front windows were smashed.
Passengers described their terror as the tourist boat collided with a tug towing two barges.
