diff --git a/tasks/install.yml b/tasks/install.yml
index 96f79a5..ded6de3 100644
--- a/tasks/install.yml
+++ b/tasks/install.yml
@@ -32,7 +32,7 @@
       template:
         src: config/credentials.ini.j2
         dest: "{{ certbot_config_dir }}/credentials.ini"
-        mode: 600
+        mode: 0600
       when: certbot_credentials | default([]) | length > 0
 
     - name: Schedule certbot run