diff --git a/build/run/installer.sh b/build/run/installer.sh
index 8f7771f..8a613fd 100755
--- a/build/run/installer.sh
+++ b/build/run/installer.sh
@@ -423,6 +423,11 @@ server {
 
     root /usr/share/webapps/roundcube;
 
+    # Add trailing slash to URI
+    location ~ ^(.+[^/])$ {
+        return 301 $scheme://$host$1/;
+    }
+
     # Postfixadmin
     location ^~ /admin/ {
         proxy_pass http://127.0.0.1:12000/;