diff --git a/homeassistant/components/nextbus/config_flow.py b/homeassistant/components/nextbus/config_flow.py
index d7149bcc9f4..000dd86eb52 100644
--- a/homeassistant/components/nextbus/config_flow.py
+++ b/homeassistant/components/nextbus/config_flow.py
@@ -58,7 +58,7 @@ def _get_stop_tags(
     # Append directions for stops with shared titles
     for tag, title in tags.items():
         if title_counts[title] > 1:
-            tags[tag] = f"{title} ({stop_directions[tag]})"
+            tags[tag] = f"{title} ({stop_directions.get(tag, tag)})"
 
     return tags
 
diff --git a/tests/components/nextbus/conftest.py b/tests/components/nextbus/conftest.py
index a38f3fd850e..0940118c13a 100644
--- a/tests/components/nextbus/conftest.py
+++ b/tests/components/nextbus/conftest.py
@@ -19,6 +19,8 @@ def mock_nextbus_lists(mock_nextbus: MagicMock) -> MagicMock:
             "stop": [
                 {"tag": "5650", "title": "Market St & 7th St"},
                 {"tag": "5651", "title": "Market St & 7th St"},
+                # Error case test. Duplicate title with no unique direction
+                {"tag": "5652", "title": "Market St & 7th St"},
             ],
             "direction": [
                 {