This painting is difficult to date, and different theories have been proposed as to its date and authenticity.

It is just possible that Young woman in a white dress was started in the early 1870s, rubbed down by Whistler at the time of his bankruptcy in 1879, and later restored by an unknown hand, as appears to have been the case with Harmony in White and Blue [YMSM 126] (and see also Arrangement in Flesh Colour and Grey: The Chinese Screen [YMSM 051]).

Young woman in a white dress, photo, 1940s

Young woman in a white dress, Singer Museum

Alternatively it may have been entirely painted by another artist, before 1910, when it is first documented. It has certainly been restored and retouched by other hands over subsequent years, up to and including 2015.