diff --git a/changes/anilist-final-episode-completion.md b/changes/anilist-final-episode-completion.md
new file mode 100644
index 00000000..854054fe
--- /dev/null
+++ b/changes/anilist-final-episode-completion.md
@@ -0,0 +1,4 @@
+type: fixed
+area: anilist
+
+- Marked AniList entries completed when a post-watch update reaches the final known episode of the season.
diff --git a/src/core/services/anilist/anilist-updater.test.ts b/src/core/services/anilist/anilist-updater.test.ts
index 9a09e689..e2376973 100644
--- a/src/core/services/anilist/anilist-updater.test.ts
+++ b/src/core/services/anilist/anilist-updater.test.ts
@@ -235,6 +235,86 @@ test('updateAnilistPostWatchProgress uses the configured AniList rate limiter',
   }
 });
 
+test('updateAnilistPostWatchProgress marks the final season episode completed', async () => {
+  const originalFetch = globalThis.fetch;
+  let call = 0;
+  globalThis.fetch = (async (_input, init) => {
+    call += 1;
+    const body = JSON.parse(String(init?.body)) as { variables?: Record<string, unknown> };
+    if (call === 1) {
+      return createJsonResponse({
+        data: {
+          Page: {
+            media: [{ id: 12, episodes: 12, title: { english: 'Final Show' } }],
+          },
+        },
+      });
+    }
+    if (call === 2) {
+      return createJsonResponse({
+        data: {
+          Media: { id: 12, mediaListEntry: { progress: 11, status: 'CURRENT' } },
+        },
+      });
+    }
+
+    assert.equal(body.variables?.progress, 12);
+    assert.equal(body.variables?.status, 'COMPLETED');
+    return createJsonResponse({
+      data: { SaveMediaListEntry: { progress: 12, status: 'COMPLETED' } },
+    });
+  }) as typeof fetch;
+
+  try {
+    const result = await updateAnilistPostWatchProgress('token', 'Final Show', 12);
+    assert.equal(result.status, 'updated');
+    assert.match(result.message, /completed/i);
+    assert.equal(call, 3);
+  } finally {
+    globalThis.fetch = originalFetch;
+  }
+});
+
+test('updateAnilistPostWatchProgress marks an already watched final season episode completed', async () => {
+  const originalFetch = globalThis.fetch;
+  let call = 0;
+  globalThis.fetch = (async (_input, init) => {
+    call += 1;
+    const body = JSON.parse(String(init?.body)) as { variables?: Record<string, unknown> };
+    if (call === 1) {
+      return createJsonResponse({
+        data: {
+          Page: {
+            media: [{ id: 12, episodes: 12, title: { english: 'Final Show' } }],
+          },
+        },
+      });
+    }
+    if (call === 2) {
+      return createJsonResponse({
+        data: {
+          Media: { id: 12, mediaListEntry: { progress: 12, status: 'CURRENT' } },
+        },
+      });
+    }
+
+    assert.equal(body.variables?.progress, 12);
+    assert.equal(body.variables?.status, 'COMPLETED');
+    return createJsonResponse({
+      data: { SaveMediaListEntry: { progress: 12, status: 'COMPLETED' } },
+    });
+  }) as typeof fetch;
+
+  try {
+    const result = await updateAnilistPostWatchProgress('token', 'Final Show', 12);
+    assert.equal(result.status, 'updated');
+    assert.match(result.message, /completed/i);
+    assert.equal(call, 3);
+  } finally {
+    globalThis.fetch = originalFetch;
+  }
+});
+
 test('updateAnilistPostWatchProgress skips when progress already reached', async () => {
   const originalFetch = globalThis.fetch;
   let call = 0;
diff --git a/src/core/services/anilist/anilist-updater.ts b/src/core/services/anilist/anilist-updater.ts
index 5956bc2e..53109eda 100644
--- a/src/core/services/anilist/anilist-updater.ts
+++ b/src/core/services/anilist/anilist-updater.ts
@@ -228,7 +228,7 @@ function pickBestSearchResult(
       native?: string | null;
     };
   }>,
-): { id: number; title: string } | null {
+): { id: number; title: string; episodes: number | null } | null {
   const filtered = media.filter((item) => {
     const totalEpisodes = item.episodes;
     return totalEpisodes === null || totalEpisodes >= episode;
@@ -247,7 +247,7 @@ function pickBestSearchResult(
   const selected = exact ?? candidates[0]!;
   const selectedTitle =
     selected.title?.english || selected.title?.romaji || selected.title?.native || title;
-  return { id: selected.id, title: selectedTitle };
+  return { id: selected.id, title: selectedTitle, episodes: selected.episodes };
 }
 
 function isUpdateableListStatus(status: string | null | undefined): boolean {
@@ -259,6 +259,15 @@ function formatListStatus(status: string | null | undefined): string {
   return `marked ${status.toLowerCase().replace(/_/g, ' ')} on AniList`;
 }
 
+function isKnownFinalEpisode(totalEpisodes: number | null, episode: number): boolean {
+  return (
+    typeof totalEpisodes === 'number' &&
+    Number.isInteger(totalEpisodes) &&
+    totalEpisodes > 0 &&
+    episode === totalEpisodes
+  );
+}
+
 export async function guessAnilistMediaInfo(
   mediaPath: string | null,
   mediaTitle: string | null,
@@ -394,7 +403,8 @@ export async function updateAnilistPostWatchProgress(
   }
 
   const currentProgress = entry.progress ?? 0;
-  if (typeof currentProgress === 'number' && currentProgress >= episode) {
+  const shouldMarkCompleted = isKnownFinalEpisode(picked.episodes, episode);
+  if (typeof currentProgress === 'number' && currentProgress >= episode && !shouldMarkCompleted) {
     return {
       status: 'skipped',
       message: `AniList already at episode ${currentProgress} (${picked.title}).`,
@@ -404,14 +414,18 @@ export async function updateAnilistPostWatchProgress(
   const saveResponse = await anilistGraphQl<AnilistSaveEntryData>(
     accessToken,
     `
-      mutation ($mediaId: Int!, $progress: Int!) {
-        SaveMediaListEntry(mediaId: $mediaId, progress: $progress, status: CURRENT) {
+      mutation ($mediaId: Int!, $progress: Int!, $status: MediaListStatus!) {
+        SaveMediaListEntry(mediaId: $mediaId, progress: $progress, status: $status) {
           progress
           status
         }
       }
     `,
-    { mediaId: picked.id, progress: episode },
+    {
+      mediaId: picked.id,
+      progress: episode,
+      status: shouldMarkCompleted ? 'COMPLETED' : 'CURRENT',
+    },
     options,
   );
   const saveError = firstErrorMessage(saveResponse);
@@ -421,6 +435,8 @@ export async function updateAnilistPostWatchProgress(
 
   return {
     status: 'updated',
-    message: `AniList updated "${picked.title}" to episode ${episode}.`,
+    message: shouldMarkCompleted
+      ? `AniList updated "${picked.title}" to episode ${episode} and marked it completed.`
+      : `AniList updated "${picked.title}" to episode ${episode}.`,
   };
 }