From Sahih Bukhari (Hadith 3096):
Narrated Abu Huraira:Allah's Messenger (ﷺ) said, "My heirs should not take even a single Dinar (i.e. anything from my property), and whatever I leave, excluding the expenditure of my wives and my laborers, will be Sadaqa (i.e. be used for charity)
Reference: Bukhari 3096