diff --git a/README.md b/README.md
index 7e1a868..1922838 100644
--- a/README.md
+++ b/README.md
@@ -86,6 +86,7 @@ Add `django-sage-invoice` to your `INSTALLED_APPS` in the Django settings and co
 ```python
 INSTALLED_APPS = [
     # other packages
+    "django.contrib.humanize",
     "django_jsonform",
     "import_export",
     "sage_tools",