diff --git a/crates/frontend/public/templates/layouts/default.html b/crates/frontend/public/templates/layouts/default.html
index 46a1388..329b116 100644
--- a/crates/frontend/public/templates/layouts/default.html
+++ b/crates/frontend/public/templates/layouts/default.html
@@ -14,9 +14,11 @@
   <header>
       <a class="logo" href="/frontend/user">RustiCal</a>
       {% block header_center %}{% endblock %}
-      <form method="POST" action="/frontend/logout" class="logout_form">
-        <button type="submit">Log out</button>
-      </form>
+      {% if self.get_user().is_some() %}
+        <form method="POST" action="/frontend/logout" class="logout_form">
+          <button type="submit">Log out</button>
+        </form>
+      {% endif %}
   </header>
   {% endblock %}
   <div id="app">
diff --git a/crates/frontend/src/nextcloud_login/routes.rs b/crates/frontend/src/nextcloud_login/routes.rs
index 773d328..b0056ad 100644
--- a/crates/frontend/src/nextcloud_login/routes.rs
+++ b/crates/frontend/src/nextcloud_login/routes.rs
@@ -2,7 +2,7 @@ use super::{
     NextcloudFlow, NextcloudFlows, NextcloudLoginPoll, NextcloudLoginResponse,
     NextcloudSuccessResponse,
 };
-use crate::routes::app_token::generate_app_token;
+use crate::{pages::DefaultLayoutData, routes::app_token::generate_app_token};
 use askama::Template;
 use axum::{
     Extension, Form, Json,
@@ -100,6 +100,12 @@ struct NextcloudLoginPage {
     app_name: String,
 }
 
+impl DefaultLayoutData for NextcloudLoginPage {
+    fn get_user(&self) -> Option<&Principal> {
+        None
+    }
+}
+
 #[instrument(skip(state))]
 pub async fn get_nextcloud_flow(
     Extension(state): Extension<Arc<NextcloudFlows>>,
@@ -130,6 +136,13 @@ pub struct NextcloudAuthorizeForm {
 #[template(path = "pages/nextcloud_login/success.html")]
 struct NextcloudLoginSuccessPage {
     app_name: String,
+    user: Principal,
+}
+
+impl DefaultLayoutData for NextcloudLoginSuccessPage {
+    fn get_user(&self) -> Option<&Principal> {
+        Some(&self.user)
+    }
 }
 
 #[instrument(skip(state))]
@@ -150,6 +163,7 @@ pub async fn post_nextcloud_flow(
         Ok(Html(
             NextcloudLoginSuccessPage {
                 app_name: flow.app_name.clone(),
+                user,
             }
             .render()
             .unwrap(),
diff --git a/crates/frontend/src/pages/mod.rs b/crates/frontend/src/pages/mod.rs
index 22d12a3..b4bad06 100644
--- a/crates/frontend/src/pages/mod.rs
+++ b/crates/frontend/src/pages/mod.rs
@@ -1 +1,8 @@
+use rustical_store::auth::Principal;
+
 pub mod user;
+
+/// Required by the base layout
+pub trait DefaultLayoutData {
+    fn get_user(&self) -> Option<&Principal>;
+}
diff --git a/crates/frontend/src/pages/user.rs b/crates/frontend/src/pages/user.rs
index e395ea0..32f71c7 100644
--- a/crates/frontend/src/pages/user.rs
+++ b/crates/frontend/src/pages/user.rs
@@ -2,6 +2,8 @@ use askama::Template;
 use askama_web::WebTemplate;
 use rustical_store::auth::Principal;
 
+use crate::pages::DefaultLayoutData;
+
 pub trait Section: Template {
     fn name() -> &'static str;
 }
@@ -12,3 +14,9 @@ pub struct UserPage<S: Section> {
     pub user: Principal,
     pub section: S,
 }
+
+impl<S: Section> DefaultLayoutData for UserPage<S> {
+    fn get_user(&self) -> Option<&Principal> {
+        Some(&self.user)
+    }
+}
diff --git a/crates/frontend/src/routes/addressbook.rs b/crates/frontend/src/routes/addressbook.rs
index 66e80d0..4e7ee38 100644
--- a/crates/frontend/src/routes/addressbook.rs
+++ b/crates/frontend/src/routes/addressbook.rs
@@ -12,10 +12,19 @@ use headers::Referer;
 use http::StatusCode;
 use rustical_store::{Addressbook, AddressbookStore, auth::Principal};
 
+use crate::pages::DefaultLayoutData;
+
 #[derive(Template, WebTemplate)]
 #[template(path = "pages/addressbook.html")]
 struct AddressbookPage {
     addressbook: Addressbook,
+    user: Principal,
+}
+
+impl DefaultLayoutData for AddressbookPage {
+    fn get_user(&self) -> Option<&Principal> {
+        Some(&self.user)
+    }
 }
 
 pub async fn route_addressbook<AS: AddressbookStore>(
@@ -28,6 +37,7 @@ pub async fn route_addressbook<AS: AddressbookStore>(
     }
     Ok(AddressbookPage {
         addressbook: store.get_addressbook(&owner, &addrbook_id, true).await?,
+        user,
     }
     .into_response())
 }
diff --git a/crates/frontend/src/routes/calendar.rs b/crates/frontend/src/routes/calendar.rs
index 37c5428..7ed9f07 100644
--- a/crates/frontend/src/routes/calendar.rs
+++ b/crates/frontend/src/routes/calendar.rs
@@ -1,5 +1,4 @@
-use std::sync::Arc;
-
+use crate::pages::DefaultLayoutData;
 use askama::Template;
 use askama_web::WebTemplate;
 use axum::{
@@ -11,11 +10,19 @@ use axum_extra::TypedHeader;
 use headers::Referer;
 use http::StatusCode;
 use rustical_store::{Calendar, CalendarStore, auth::Principal};
+use std::sync::Arc;
 
 #[derive(Template, WebTemplate)]
 #[template(path = "pages/calendar.html")]
 struct CalendarPage {
     calendar: Calendar,
+    user: Principal,
+}
+
+impl DefaultLayoutData for CalendarPage {
+    fn get_user(&self) -> Option<&Principal> {
+        Some(&self.user)
+    }
 }
 
 pub async fn route_calendar<C: CalendarStore>(
@@ -28,6 +35,7 @@ pub async fn route_calendar<C: CalendarStore>(
     }
     Ok(CalendarPage {
         calendar: store.get_calendar(&owner, &cal_id, true).await?,
+        user,
     }
     .into_response())
 }
diff --git a/crates/frontend/src/routes/login.rs b/crates/frontend/src/routes/login.rs
index 66eab34..39682c5 100644
--- a/crates/frontend/src/routes/login.rs
+++ b/crates/frontend/src/routes/login.rs
@@ -1,6 +1,6 @@
 use std::sync::Arc;
 
-use crate::{FrontendConfig, OidcConfig};
+use crate::{FrontendConfig, OidcConfig, pages::DefaultLayoutData};
 use askama::Template;
 use askama_web::WebTemplate;
 use axum::{
@@ -24,6 +24,12 @@ struct LoginPage<'a> {
     allow_password_login: bool,
 }
 
+impl DefaultLayoutData for LoginPage<'_> {
+    fn get_user(&self) -> Option<&rustical_store::auth::Principal> {
+        None
+    }
+}
+
 struct OidcProviderData<'a> {
     pub name: &'a str,
     pub redirect_url: String,