diff --git a/core/admin/mailu/ui/templates/user/signup.html b/core/admin/mailu/ui/templates/user/signup.html
index 59c1a988..f540d660 100644
--- a/core/admin/mailu/ui/templates/user/signup.html
+++ b/core/admin/mailu/ui/templates/user/signup.html
@@ -14,7 +14,9 @@
   {% call macros.box() %}
   {{ macros.form_field(form.localpart, append='<span class="input-group-addon">@'+domain.name+'</span>') }}
   {{ macros.form_fields((form.pw, form.pw2)) }}
-  {{ macros.form_field(form.captcha) }}
+  {% if form.captcha %}
+    {{ macros.form_field(form.captcha) }}
+  {% endif %}
   {{ macros.form_field(form.submit) }}
   {% endcall %}
 </form>