The 5e *[Unearthed Arcana: Eberron][1]* (v1.1) says:

> Although they are constructs, they have much in common with living creatures, including emotions and social bonds, and **perhaps even souls.**

This last part troubles me, however. 

**Do warforged canonically have souls?**


  [1]: https://media.wizards.com/2015/downloads/dnd/UA_Eberron_v1.1.pdf#page=3