Agnes Brotherston, 75, was found in her home in Strathaven, South Lanarkshire, last November after police were called to the property.
Neighbours of Mrs Brotherston, who lived alone, had raised the alarm after complaining about a strange smell and bluebottle flies.
It was thought she may have been dead since the summer but was only discovered when police officers entered the property.
It has now emerged that she had a fortune of £936,309.
In her published will, Mrs Brotherston instructed that the money should go to her two daughters Helen McInnes, of Glasgow, and Jane Dyer, from Cheshire.
A report has been sent to the procurator-fiscal.