diff --git a/docs/redirects.json b/docs/redirects.json
index 6ddfdaa..5d127af 100644
--- a/docs/redirects.json
+++ b/docs/redirects.json
@@ -4835,9 +4835,6 @@
   "services-nextcloudserver-options-shb.nextcloud.adminPass.result.path": [
     "services-nextcloud.html#services-nextcloudserver-options-shb.nextcloud.adminPass.result.path"
   ],
-  "services-nextcloudserver-options-shb.nextcloud.adminUser": [
-    "services-nextcloud.html#services-nextcloudserver-options-shb.nextcloud.adminUser"
-  ],
   "services-nextcloudserver-options-shb.nextcloud.alwaysApplyExpensiveMigrations": [
     "services-nextcloud.html#services-nextcloudserver-options-shb.nextcloud.alwaysApplyExpensiveMigrations"
   ],
@@ -5117,6 +5114,9 @@
   "services-nextcloudserver-options-shb.nextcloud.extraApps": [
     "services-nextcloud.html#services-nextcloudserver-options-shb.nextcloud.extraApps"
   ],
+  "services-nextcloudserver-options-shb.nextcloud.initialAdminUsername": [
+    "services-nextcloud.html#services-nextcloudserver-options-shb.nextcloud.initialAdminUsername"
+  ],
   "services-nextcloudserver-options-shb.nextcloud.maxUploadSize": [
     "services-nextcloud.html#services-nextcloudserver-options-shb.nextcloud.maxUploadSize"
   ],
diff --git a/modules/services/nextcloud-server.nix b/modules/services/nextcloud-server.nix
index e902807..6b160a3 100644
--- a/modules/services/nextcloud-server.nix
+++ b/modules/services/nextcloud-server.nix
@@ -30,6 +30,11 @@ in
     ../../lib/module.nix
     ../blocks/authelia.nix
     ../blocks/monitoring.nix
+
+    (lib.mkRenamedOptionModule
+      [ "shb" "nextcloud" "adminUser" ]
+      [ "shb" "nextcloud" "initialAdminUsername" ]
+    )
   ];
 
   options.shb.nextcloud = {
@@ -110,9 +115,9 @@ in
       example = lib.literalExpression ''["var.mount"]'';
     };
 
-    adminUser = lib.mkOption {
+    initialAdminUsername = lib.mkOption {
       type = lib.types.str;
-      description = "Username of the initial admin user.";
+      description = "Initial username of the admin user. Once it is set, it cannot be changed!";
       default = "root";
     };
 
@@ -758,7 +763,7 @@ in
 
         config = {
           dbtype = "pgsql";
-          adminuser = cfg.adminUser;
+          adminuser = cfg.initialAdminUsername;
           adminpassFile = cfg.adminPass.result.path;
         };
         database.createLocally = true;
diff --git a/modules/services/nextcloud-server/docs/default.md b/modules/services/nextcloud-server/docs/default.md
index 957e3b2..faeacc6 100644
--- a/modules/services/nextcloud-server/docs/default.md
+++ b/modules/services/nextcloud-server/docs/default.md
@@ -72,6 +72,7 @@ shb.nextcloud = {
   domain = "example.com";
   subdomain = "n";
   defaultPhoneRegion = "US";
+  initialAdminUsername = "root";
   adminPass.result = config.shb.sops.secret."nextcloud/adminpass".result;
 };
 
@@ -85,7 +86,7 @@ Note though that Nextcloud will not be very happy to be accessed through HTTP,
 it much prefers - rightfully - to be accessed through HTTPS.
 We will set that up in the next section.
 
-You can now login as the admin user using the username `admin`
+You can now login as the admin user using the username `root`
 and the password defined in `sops.secrets."nextcloud/adminpass"`.
 
 ### Nextcloud through HTTPS {#services-nextcloudserver-usage-https}