diff --git a/src/stores/TagOrderStore.js b/src/stores/TagOrderStore.js
index 820634b90e..633ffc7e9c 100644
--- a/src/stores/TagOrderStore.js
+++ b/src/stores/TagOrderStore.js
@@ -31,7 +31,7 @@ class TagOrderStore extends Store {
         super(dis);
 
         // Initialise state
-        this._state = INITIAL_STATE;
+        this._state = Object.assign({}, INITIAL_STATE);
     }
 
     _setState(newState) {
@@ -93,6 +93,12 @@ class TagOrderStore extends Store {
                 this._setState({orderedTags});
                 break;
             }
+            case 'on_logged_out': {
+                // Reset state without pushing an update to the view, which generally assumes that
+                // the matrix client isn't `null` and so causing a re-render will cause NPEs.
+                this._state = Object.assign({}, INITIAL_STATE);
+                break;
+            }
         }
     }