diff --git a/runtox.py b/runtox.py
index 94e80ba4f..40fbcb569 100644
--- a/runtox.py
+++ b/runtox.py
@@ -4,7 +4,7 @@ import subprocess
 import sys
 
 if __name__ == "__main__":
-    subprocess.call(["tox",
+    subprocess.call([sys.executable, "-m", "tox",
                      "-i", "ALL=https://devpi.net/hpk/dev/",
                      "--develop",] + sys.argv[1:])