diff --git a/script/cpp_unit_test.py b/script/cpp_unit_test.py
index 78b65092ae..02b133060a 100755
--- a/script/cpp_unit_test.py
+++ b/script/cpp_unit_test.py
@@ -98,8 +98,12 @@ def run_tests(selected_components: list[str]) -> int:
 
     components = sorted(components)
 
-    # Obtain possible dependencies for the requested components:
-    components_with_dependencies = sorted(get_all_dependencies(set(components)))
+    # Obtain possible dependencies for the requested components.
+    # Always include 'time' because USE_TIME_TIMEZONE is defined as a build flag,
+    # which causes core/time.h to include components/time/posix_tz.h.
+    components_with_dependencies = sorted(
+        get_all_dependencies(set(components) | {"time"})
+    )
 
     # Build a list of include folders, one folder per component containing tests.
     # A special replacement main.cpp is located in /tests/components/main.cpp