diff --git a/app/pages/changelog/[slug].vue b/app/pages/changelog/[slug].vue
index 28cbe1e9..b56f4f45 100644
--- a/app/pages/changelog/[slug].vue
+++ b/app/pages/changelog/[slug].vue
@@ -21,6 +21,11 @@ const slug = route.params.slug as string
 
 const { data: entry, error } = await useFetch<ChangelogListItem>(`/api/changelogs/${slug}`)
 
+// Keep the not-found message, but answer 404 like the help article page does.
+if (import.meta.server && error.value) {
+  setResponseStatus(useRequestEvent()!, 404)
+}
+
 const coverUrl = computed(() => resolveAttachmentUrl(entry.value?.cover))
 
 const timeAgo = useTimeAgo()
diff --git a/app/pages/p/[slug].vue b/app/pages/p/[slug].vue
index 7e2dac5e..44df4930 100644
--- a/app/pages/p/[slug].vue
+++ b/app/pages/p/[slug].vue
@@ -9,7 +9,12 @@ const boardStore = useBoardStore()
 await callOnce(() => boardStore.fetchBoards())
 
 // SSR: fetch via useFetch (payload auto-transferred), then hydrate store on both sides
-const { data: postData } = await useFetch<PostDetail>(`/api/posts/${slug}`)
+const { data: postData, error: postError } = await useFetch<PostDetail>(`/api/posts/${slug}`)
+// A missing post is a 404, not an empty page with 200 (a "soft 404" that search
+// engines index and link checkers cannot see).
+if (postError.value?.statusCode === 404) {
+  throw createError({ statusCode: 404, statusMessage: 'Not Found', fatal: true })
+}
 if (postData.value) {
   store.setPost(slug, postData.value)
 }