diff --git a/esphome/config_validation.py b/esphome/config_validation.py
index 3aebca81b8..61ef7d2f9f 100644
--- a/esphome/config_validation.py
+++ b/esphome/config_validation.py
@@ -1457,7 +1457,11 @@ class OnlyWith(Optional):
         if self._component in CORE.raw_config or (
             CONF_PACKAGES in CORE.raw_config
             and self._component
-            in {list(x.keys())[0] for x in CORE.raw_config[CONF_PACKAGES].values()}
+            in [
+                k
+                for package in CORE.raw_config[CONF_PACKAGES].values()
+                for k in package.keys()
+            ]
         ):
             return self._default
         return vol.UNDEFINED