diff --git a/src/cargotype.cpp b/src/cargotype.cpp
index f6509dd389..95c9708d4a 100644
--- a/src/cargotype.cpp
+++ b/src/cargotype.cpp
@@ -102,7 +102,7 @@ void BuildCargoLabelMap()
 	_cargo_label_map.clear();
 	for (const CargoSpec &cs : CargoSpec::array) {
 		/* During initialization, CargoSpec can be marked valid before the label has been set. */
-		if (!cs.IsValid() || cs.label == CargoLabel{0}) continue;
+		if (!cs.IsValid() || cs.label == CargoLabel{0} || cs.label == CT_INVALID) continue;
 		/* Label already exists, don't add again. */
 		if (_cargo_label_map.count(cs.label) != 0) continue;