diff --git a/tasks/users_default.yml b/tasks/users_default.yml
index 9b3efb7..c2e0068 100644
--- a/tasks/users_default.yml
+++ b/tasks/users_default.yml
@@ -10,7 +10,7 @@
       user:
         name: "{{ item.name }}"
         groups: "{{ item.groups | default([]) | join(',') or omit }}"
-        append: yes
+        append: "{{ True if (item.groups | default([]) | length > 0) else False }}"
         password: "{{ item.password | password_hash('sha512',65534 | random(seed=inventory_hostname) | string) if item.password is defined else omit }}"
         shell: "{{ item.shell | default('/bin/bash') }}"
       loop: "{{ users_default_users }}"
diff --git a/tasks/users_univention.yml b/tasks/users_univention.yml
index 8bbacc3..84627c6 100644
--- a/tasks/users_univention.yml
+++ b/tasks/users_univention.yml
@@ -13,7 +13,7 @@
       user:
         name: "{{ item.name }}"
         groups: "{{ item.groups | default([]) | join(',') or omit }}"
-        append: yes
+        append: "{{ True if (item.groups | default([]) | length > 0) else False }}"
         password: "{{ item.password | default(omit) | password_hash('sha512',65534 | random(seed=inventory_hostname) | string) }}"
         shell: "{{ item.shell | default('/bin/bash') }}"
         system: 'yes'