They find Will Byers at the very end of Stranger Things Season 1, in the episode titled “Chapter Eight: The Upside Down.”

Quick answer

  • Will disappears on November 6, 1983 , in Episode 1, “The Vanishing of Will Byers.”
  • Joyce and Hopper physically find and rescue him in the Upside Down around November 12–13, 1983 , during the Season 1 finale, “Chapter Eight: The Upside Down.”

So, in terms of episode count, they find him in Season 1, Episode 8 , right at the climax of the first season.

Mini timeline in the show

  • Episode 1 – “The Vanishing of Will Byers” : Will goes missing after encountering the Demogorgon on his bike ride home on November 6, 1983.
  • Mid‑season : Joyce realizes he’s in the Upside Down and communicates through lights and the wall in her house.
  • Episode 8 – “The Upside Down” : Joyce and Hopper cross into the Upside Down, find Will, and revive him with CPR, bringing him back to Hawkins.

Meta description:
Wondering when do they find Will Byers in Stranger Things? Will is finally found and rescued in the Season 1 finale, Episode 8, “The Upside Down,” after vanishing on November 6, 1983.

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