diff --git a/rumqttc/src/state.rs b/rumqttc/src/state.rs
index cc9346c1c..f0cee54d8 100644
--- a/rumqttc/src/state.rs
+++ b/rumqttc/src/state.rs
@@ -471,6 +471,7 @@ impl MqttState {
         };
 
         self.outgoing_rel[pubrel.pkid as usize] = Some(pubrel.pkid);
+        self.inflight += 1;
         Ok(pubrel)
     }