Where to start the Demon Slayer manga after the anime

Give it the last episode you watched. The mappings cover whole seasons. At a season boundary, the answer gives the next unread chapter; within a season, it gives a conservative starting point that may repeat material.

Every span the anime adapts

One row per season or film: the episodes, the chapters they adapt, and a note on where the boundary falls.

AnimeEpisodesChaptersNote
Demon Slayer: Kimetsu no Yaiba Film: Mugen Train—54–66The 2020 film. It stops at chapter 66, three chapters short of where the manga's Mugen Train arc ends: Tanjiro's visit to the Rengoku house is held back for episode 34.
Demon Slayer: Kimetsu no Yaiba Film: Infinity Castle – Part 1—140–157The 2025 film, the first of three. No published source gives its chapter range: it opens the Infinity Castle arc at chapter 140 and ends on Akaza's death, which is chapter 157. Treat the upper bound as approximate, since the film may reach into 158.
Demon Slayer: Kimetsu no Yaiba Season 1: Tanjiro Kamado, Unwavering Resolve Arc1–261–54Episode 26 opens on chapter 54, one chapter past the end of the Unwavering Resolve arc as the manga draws it.
Demon Slayer: Kimetsu no Yaiba Season 2: Mugen Train Arc27–3354–66A television recut of the 2020 film with one new episode, so it covers the same chapters and stops at 66 rather than at the manga arc's end.
Demon Slayer: Kimetsu no Yaiba Season 2: Entertainment District Arc34–4467–97Opens at chapter 67 rather than at the arc's own first chapter, 70, because episode 34 adapts the Rengoku house visit the film left out.
Demon Slayer: Kimetsu no Yaiba Season 3: Swordsmith Village Arc45–5598–127Chapters 98 to 127, which is volumes 12 to 15.
Demon Slayer: Kimetsu no Yaiba Season 4: Hashira Training Arc56–63128–139Chapters 128 to 139, which is volumes 15 and 16.

Every Demon Slayer volume, with its chapters