Just one day after the first trailer for Spider-Man: Homecoming was released, Sony has already announced an opening date for a sequel to the solo film. According to Deadline, the film in now slated to hit theatres July 5th, 2019 — almost exactly two years after Homecoming. That also puts the film out two months after the fourth yet-untitled Avengers film.
Interestingly, the film is currently being referred to Spider-Man: Homecoming 2, although
that is likely a placeholder title and subject to change. In the meantime, Spider-Man: Homecoming 1 will swing into theatres July 7th, 2017.