During the second half of his career, Wilson was competing with a growing number of professional photographers hoping to emulate his success. However, he was awarded a royal warrant in 1873, which undoubtedly helped cement Wilson’s status as the leading photographer of Scotland. In 1877, he opened Wilson & Co., one of the largest photographic printing works in the world, at St Swithin’s Street in Aberdeen.

Wilson retired in 1888, as his health declined, to pursue his first love of painting. A year earlier his youngest son, Charles Wilson, aged 23, had successfully applied to succeed his father as ‘Photographer to Her Majesty in Scotland’. Some of the last royal photographs taken under the Wilson & Co. company name were of various tableaux performed at Balmoral in 1888 and 1893. In November 1893, Robert Milne (1865–1952) was appointed as the ‘New Photographer at Balmoral’.

Wilson died on 9 March 1893. He had enjoyed an illustrious career as a royal photographer for nearly 35 years. The Wilson & Co. business continued for some years, run by his sons, before closing for good in 1908. Wilson’s surviving negatives are now housed by the University of Aberdeen.