diff --git a/crates/adapters/activitypub-base/src/activities.rs b/crates/adapters/activitypub-base/src/activities.rs
index 1b2f41c..203a3a9 100644
--- a/crates/adapters/activitypub-base/src/activities.rs
+++ b/crates/adapters/activitypub-base/src/activities.rs
@@ -341,7 +341,14 @@ impl Activity for CreateActivity {
             tracing::info!(actor = %self.actor(), "ignoring activity from blocked domain");
             return Ok(());
         }
-        let ap_id = self.id.clone();
+        // Use the Note's own id, not the Create activity id (which ends in /activity).
+        // Delete activities reference the Note id, so they must match.
+        let ap_id = self
+            .object
+            .get("id")
+            .and_then(|v| v.as_str())
+            .and_then(|s| Url::parse(s).ok())
+            .unwrap_or_else(|| self.id.clone());
         let actor_url = self.actor.inner().clone();
         data.object_handler
             .on_create(&ap_id, &actor_url, self.object)