diff --git a/codex-rs/tui/src/app/app_server_events.rs b/codex-rs/tui/src/app/app_server_events.rs
index 5fb53fdc8c..3613314e65 100644
--- a/codex-rs/tui/src/app/app_server_events.rs
+++ b/codex-rs/tui/src/app/app_server_events.rs
@@ -306,6 +306,7 @@ impl App {
                 self.agents_overview.usage_disabled = false;
                 self.repaint_agents_overview();
                 self.chat_widget.cyber_policy_notice = Default::default();
+                self.chat_widget.invalidate_security_setup();
                 if let Some(crate::pager_overlay::Overlay::Analytics(view)) = &mut self.overlay {
                     view.refresh();
                 }
@@ -340,6 +341,12 @@ impl App {
                     has_codex_backend_auth,
                 );
                 if self.chat_widget.has_chatgpt_account() {
+                    crate::security_setup::prefetch(
+                        &self.config,
+                        app_server_client,
+                        self.app_event_tx.clone(),
+                        self.chat_widget.security_setup_request_id,
+                    );
                     crate::daybreak::prefetch_notice(
                         &self.config,
                         app_server_client,
diff --git a/codex-rs/tui/src/app/event_dispatch.rs b/codex-rs/tui/src/app/event_dispatch.rs
index 4a97366d41..ae51fc91be 100644
--- a/codex-rs/tui/src/app/event_dispatch.rs
+++ b/codex-rs/tui/src/app/event_dispatch.rs
@@ -1236,6 +1236,12 @@ impl App {
                         elicitation_target: None,
                     });
             }
+            AppEvent::SecuritySetupLoaded { request_id, identity, notice } => {
+                tracing::debug!(current = request_id == self.chat_widget.security_setup_request_id, "handling security setup notice");
+                if request_id == self.chat_widget.security_setup_request_id {
+                    self.chat_widget.show_security_setup(identity, notice);
+                }
+            }
             AppEvent::OpenUrlInBrowser { url } => {
                 self.open_url_in_browser(url);
             }
diff --git a/codex-rs/tui/src/app/reconnect.rs b/codex-rs/tui/src/app/reconnect.rs
index bf07b73720..513d01fb2b 100644
--- a/codex-rs/tui/src/app/reconnect.rs
+++ b/codex-rs/tui/src/app/reconnect.rs
@@ -478,6 +478,12 @@ impl App {
             matches!(bootstrap.auth_mode, Some(TelemetryAuthMode::Chatgpt)),
         );
         if self.chat_widget.has_chatgpt_account() {
+            crate::security_setup::prefetch(
+                &self.config,
+                app_server,
+                self.app_event_tx.clone(),
+                self.chat_widget.security_setup_request_id,
+            );
             crate::daybreak::prefetch_notice(
                 &self.config,
                 app_server,
diff --git a/codex-rs/tui/src/app/session_lifecycle.rs b/codex-rs/tui/src/app/session_lifecycle.rs
index 6e73c002e4..ea02b08dfe 100644
--- a/codex-rs/tui/src/app/session_lifecycle.rs
+++ b/codex-rs/tui/src/app/session_lifecycle.rs
@@ -519,6 +519,7 @@ impl App {
             AppServerTarget::LocalDaemon { .. }
         ));
         chat_widget.inherit_backend_banner_state(&mut self.chat_widget);
+        chat_widget.inherit_security_setup(&mut self.chat_widget);
         for (thread_id, entry) in self.agent_navigation.ordered_threads() {
             chat_widget.set_collab_agent_metadata(
                 thread_id,
diff --git a/codex-rs/tui/src/app/startup.rs b/codex-rs/tui/src/app/startup.rs
index f9da39c26c..5d2ad0c09f 100644
--- a/codex-rs/tui/src/app/startup.rs
+++ b/codex-rs/tui/src/app/startup.rs
@@ -985,6 +985,12 @@ See the Codex keymap documentation for supported actions and examples."
         // already has data and available reset credits can be surfaced, without
         // delaying the initial frame render.
         if requires_openai_auth && has_chatgpt_account {
+            crate::security_setup::prefetch(
+                &app.config,
+                &app_server,
+                app.app_event_tx.clone(),
+                app.chat_widget.security_setup_request_id,
+            );
             crate::daybreak::prefetch_notice(
                 &app.config,
                 &app_server,
diff --git a/codex-rs/tui/src/app/tests.rs b/codex-rs/tui/src/app/tests.rs
index a25fcabd69..2d4031e67b 100644
--- a/codex-rs/tui/src/app/tests.rs
+++ b/codex-rs/tui/src/app/tests.rs
@@ -4,6 +4,8 @@
 mod daybreak_tests;
 #[path = "tests/math_interruption_tests.rs"]
 mod math_interruption_tests;
+#[path = "tests/security_setup_tests.rs"]
+mod security_setup_tests;
 
 #[path = "tests/advanced_reasoning_tests.rs"]
 mod advanced_reasoning_tests;
diff --git a/codex-rs/tui/src/app/tests/security_setup_tests.rs b/codex-rs/tui/src/app/tests/security_setup_tests.rs
new file mode 100644
index 0000000000..b2e8bf8f1d
--- /dev/null
+++ b/codex-rs/tui/src/app/tests/security_setup_tests.rs
@@ -0,0 +1,242 @@
+//! Exercises the authenticated reminder transport against a local HTTP fixture.
+use super::disconnect::serve_reconnect_requests;
+use super::*;
+use crate::app_server_session::ThreadParamsMode;
+use crate::security_setup::Identity;
+use app_test_support::ChatGptAuthFixture;
+use app_test_support::write_chatgpt_auth;
+use codex_app_server_client::AppServerEvent;
+use codex_app_server_protocol::AccountUpdatedNotification;
+use codex_app_server_protocol::AuthMode;
+use codex_login::AuthCredentialsStoreMode;
+use pretty_assertions::assert_eq;
+use serde_json::json;
+use tokio::net::TcpListener;
+
+#[tokio::test]
+async fn security_setup_fetch_with_default_features_uses_authenticated_codex_endpoint() -> Result<()>
+{
+    let (mut app, mut events, _ops) = make_test_app_with_channels().await;
+    let backend = wiremock::MockServer::start().await;
+    app.config.chatgpt_base_url = backend.uri();
+    app.config.cli_auth_credentials_store_mode = AuthCredentialsStoreMode::File;
+    std::fs::write(
+        app.config.codex_home.join("config.toml"),
+        format!("chatgpt_base_url = {:?}\n", backend.uri()),
+    )?;
+    write_chatgpt_auth(
+        &app.config.codex_home,
+        ChatGptAuthFixture::new("test-token")
+            .account_id("account")
+            .chatgpt_user_id("user"),
+        AuthCredentialsStoreMode::File,
+    )
+    .expect("write synthetic auth");
+    app_test_support::mount_workspace_routing(&backend).await;
+    let mut server = Box::pin(crate::start_embedded_app_server_for_picker(&app.config)).await?;
+    wiremock::Mock::given(wiremock::matchers::path("/wham/security-setup"))
+        .and(wiremock::matchers::header(
+            "authorization",
+            "Bearer test-token",
+        ))
+        .and(wiremock::matchers::header("ChatGPT-Account-ID", "account"))
+        .and(wiremock::matchers::header(
+            "User-Agent",
+            codex_login::default_client::get_codex_user_agent(),
+        ))
+        .respond_with(wiremock::ResponseTemplate::new(200).set_body_json(json!({
+            "notice": {
+                "title": "Keep using Daybreak mode", "description": "Set up security.",
+                "action": {"label": "Set up security", "url": "https://chatgpt.com/cyber"}
+            }
+        })))
+        .expect(3)
+        .mount(&backend)
+        .await;
+    let request_id = app.chat_widget.security_setup_request_id;
+    let mut tui = crate::tui::test_support::make_test_tui()?;
+    let init = app.chatwidget_init_for_forked_or_resumed_thread(
+        &mut tui,
+        app.config.clone(),
+        /*initial_user_message*/ None,
+    );
+    app.replace_chat_widget(ChatWidget::new_with_app_event(init));
+    assert_eq!(app.chat_widget.security_setup_request_id, request_id);
+    crate::security_setup::prefetch(&app.config, &server, app.app_event_tx.clone(), request_id);
+    let notice = tokio::time::timeout(Duration::from_secs(5), async {
+        loop {
+            if let AppEvent::SecuritySetupLoaded {
+                request_id: actual,
+                identity,
+                notice,
+            } = events.recv().await.unwrap()
+            {
+                assert_eq!(actual, request_id);
+                assert_eq!(
+                    identity,
+                    Identity {
+                        account: "account".into(),
+                        user: "user".into()
+                    }
+                );
+                break notice;
+            }
+        }
+    })
+    .await?;
+    assert!(notice.valid());
+    let identity = Identity {
+        account: "account".into(),
+        user: "user".into(),
+    };
+    app.handle_event(
+        &mut tui,
+        &mut server,
+        AppEvent::SecuritySetupLoaded {
+            request_id,
+            identity: identity.clone(),
+            notice: notice.clone(),
+        },
+    )
+    .await?;
+    assert!(render_bottom_popup(&app.chat_widget, /*width*/ 70).contains("Set up security"));
+    app.chat_widget
+        .handle_key_event(KeyEvent::new(KeyCode::Esc, KeyModifiers::NONE));
+    assert!(!render_bottom_popup(&app.chat_widget, /*width*/ 70).contains("Set up security"));
+
+    // Reconnect can emit AccountUpdated for the same identity more than once.
+    for _ in 0..2 {
+        let stale_request_id = app.chat_widget.security_setup_request_id;
+        app.handle_app_server_event(
+            &server,
+            AppServerEvent::ServerNotification(Box::new(ServerNotification::AccountUpdated(
+                AccountUpdatedNotification {
+                    auth_mode: Some(AuthMode::Chatgpt),
+                    plan_type: None,
+                },
+            ))),
+        )
+        .await;
+        let request_id = app.chat_widget.security_setup_request_id;
+        assert_ne!(request_id, stale_request_id);
+        app.handle_event(
+            &mut tui,
+            &mut server,
+            AppEvent::SecuritySetupLoaded {
+                request_id: stale_request_id,
+                identity: Identity {
+                    account: "stale-account".into(),
+                    ..identity.clone()
+                },
+                notice: notice.clone(),
+            },
+        )
+        .await?;
+        assert!(!render_bottom_popup(&app.chat_widget, /*width*/ 70).contains("Set up security"));
+
+        let init = app.chatwidget_init_for_forked_or_resumed_thread(
+            &mut tui,
+            app.config.clone(),
+            /*initial_user_message*/ None,
+        );
+        app.replace_chat_widget(ChatWidget::new_with_app_event(init));
+        let event = tokio::time::timeout(Duration::from_secs(5), async {
+            loop {
+                let event = events.recv().await.unwrap();
+                if let AppEvent::SecuritySetupLoaded {
+                    request_id: actual,
+                    identity: actual_identity,
+                    ..
+                } = &event
+                {
+                    assert_eq!(*actual, request_id);
+                    assert_eq!(actual_identity, &identity);
+                    break event;
+                }
+            }
+        })
+        .await?;
+        app.handle_event(&mut tui, &mut server, event).await?;
+        assert!(!render_bottom_popup(&app.chat_widget, /*width*/ 70).contains("Set up security"));
+    }
+    backend.verify().await;
+    server.shutdown().await?;
+    Ok(())
+}
+
+#[tokio::test]
+async fn security_setup_skips_fetch_when_server_auth_does_not_match_saved_login() -> Result<()> {
+    for (auth_method, auth_token) in [
+        (
+            Some(AuthMode::ChatgptAuthTokens),
+            Some("other-account-token"),
+        ),
+        (Some(AuthMode::ChatgptAuthTokens), Some("saved-token")),
+        (Some(AuthMode::Chatgpt), Some("other-account-token")),
+        (Some(AuthMode::Chatgpt), None),
+        (None, None),
+    ] {
+        let (mut app, _events, _ops) = make_test_app_with_channels().await;
+        let backend = wiremock::MockServer::start().await;
+        app.config.chatgpt_base_url = backend.uri();
+        app.config.cli_auth_credentials_store_mode = AuthCredentialsStoreMode::File;
+        write_chatgpt_auth(
+            &app.config.codex_home,
+            ChatGptAuthFixture::new("saved-token")
+                .account_id("saved-account")
+                .chatgpt_user_id("saved-user"),
+            AuthCredentialsStoreMode::File,
+        )
+        .expect("write synthetic auth");
+        wiremock::Mock::given(wiremock::matchers::path("/wham/security-setup"))
+            .respond_with(wiremock::ResponseTemplate::new(200).set_body_json(json!({
+                "notice": {
+                    "title": "Keep using Daybreak mode", "description": "Set up security.",
+                    "action": {"label": "Set up security", "url": "https://chatgpt.com/cyber"}
+                }
+            })))
+            .expect(0)
+            .mount(&backend)
+            .await;
+
+        let listener = TcpListener::bind("127.0.0.1:0").await?;
+        let endpoint = crate::resolve_remote_addr(&format!("ws://{}", listener.local_addr()?))?;
+        let daemon = tokio::spawn(async move {
+            let (stream, _) = listener.accept().await?;
+            serve_reconnect_requests(tokio_tungstenite::accept_async(stream).await?, |request| {
+                assert_eq!(request.method, "getAuthStatus");
+                assert_eq!(
+                    request.params,
+                    Some(json!({"includeToken": true, "refreshToken": false}))
+                );
+                std::future::ready(Some(json!({"result": {
+                    "authMethod": auth_method, "authToken": auth_token,
+                    "requiresOpenaiAuth": true
+                }})))
+            })
+            .await
+        });
+        let server = AppServerSession::new(
+            crate::connect_remote_app_server(endpoint).await?,
+            ThreadParamsMode::Embedded,
+        );
+        let (tx, mut events) = mpsc::unbounded_channel();
+        crate::security_setup::prefetch(
+            &app.config,
+            &server,
+            AppEventSender::new(tx),
+            app.chat_widget.security_setup_request_id,
+        );
+        // The fetch owns the only sender, so channel closure proves it completed.
+        assert!(
+            tokio::time::timeout(Duration::from_secs(5), events.recv())
+                .await?
+                .is_none()
+        );
+        backend.verify().await;
+        server.shutdown().await?;
+        let methods = daemon.await??;
+        assert!(methods.iter().any(|method| method == "getAuthStatus"));
+    }
+    Ok(())
+}
diff --git a/codex-rs/tui/src/app_event.rs b/codex-rs/tui/src/app_event.rs
index 982c3ecb5a..0d160fd8f5 100644
--- a/codex-rs/tui/src/app_event.rs
+++ b/codex-rs/tui/src/app_event.rs
@@ -277,6 +277,11 @@ pub(crate) struct AgentsOverviewThreadRefresh {
 #[allow(clippy::large_enum_variant)]
 #[derive(Debug, IntoStaticStr)]
 pub(crate) enum AppEvent {
+    SecuritySetupLoaded {
+        request_id: uuid::Uuid,
+        identity: crate::security_setup::Identity,
+        notice: crate::security_setup::Notice,
+    },
     OpenDaemonMenu,
     ConfirmDaemonUpdate(crate::update_action::DaemonUpdateSource),
     RunDaemonUpdate(crate::update_action::DaemonUpdateSource),
diff --git a/codex-rs/tui/src/bottom_pane/actionable_banner.rs b/codex-rs/tui/src/bottom_pane/actionable_banner.rs
index 5bcdbfd8f7..a7d7c327da 100644
--- a/codex-rs/tui/src/bottom_pane/actionable_banner.rs
+++ b/codex-rs/tui/src/bottom_pane/actionable_banner.rs
@@ -159,6 +159,16 @@ impl From<ActionableBanner> for SelectionViewParams {
 }
 
 impl BottomPane {
+    pub(crate) fn transfer_inline_banner_from(&mut self, previous: &mut Self) {
+        self.inline_banner = previous.inline_banner.take();
+        if let Some(banner) = &mut self.inline_banner
+            && let InlineBannerContent::Actions(view) = &mut banner.content
+        {
+            view.app_event_tx = self.app_event_tx.clone();
+        }
+        self.request_redraw();
+    }
+
     pub(crate) fn show_actionable_banner(&mut self, banner: ActionableBanner) {
         self.show_selection_view(banner.into());
     }
diff --git a/codex-rs/tui/src/bottom_pane/list_selection_view.rs b/codex-rs/tui/src/bottom_pane/list_selection_view.rs
index 575a7ea332..59603894b4 100644
--- a/codex-rs/tui/src/bottom_pane/list_selection_view.rs
+++ b/codex-rs/tui/src/bottom_pane/list_selection_view.rs
@@ -304,7 +304,7 @@ pub(crate) struct ListSelectionView {
     state: ScrollState,
     completion: Option<ViewCompletion>,
     pub(super) dismiss_after_child_accept: bool,
-    app_event_tx: AppEventSender,
+    pub(super) app_event_tx: AppEventSender,
     is_searchable: bool,
     search_query: String,
     search_placeholder: Option<String>,
diff --git a/codex-rs/tui/src/chatwidget.rs b/codex-rs/tui/src/chatwidget.rs
index eb9c9cdfa2..15778d90e5 100644
--- a/codex-rs/tui/src/chatwidget.rs
+++ b/codex-rs/tui/src/chatwidget.rs
@@ -336,6 +336,7 @@ mod backend_banners;
 mod compaction;
 mod luna_reserve_model;
 mod luna_reserve_return;
+mod security_setup;
 pub(crate) use backend_banners::AutomaticModelSwitchReason;
 mod protocol;
 mod protocol_requests;
@@ -573,6 +574,10 @@ pub(crate) struct ChatWidget {
     clock_format: crate::clock_format::ClockFormat,
     usage_notice_state: usage_notice::UsageNoticeState,
     backend_banner_state: backend_banners::BackendBannerState,
+    pub(crate) security_setup_request_id: uuid::Uuid,
+    security_setup_presented: bool,
+    security_setup_identity: Option<crate::security_setup::Identity>,
+    security_setup_dismissed: bool,
     automatic_model_switch_state: backend_banners::AutomaticModelSwitchState,
     backend_banner_notice_model: Option<String>,
     // Remember the account's Reserve entry notice across chats and transient banner refreshes.
diff --git a/codex-rs/tui/src/chatwidget/backend_banners.rs b/codex-rs/tui/src/chatwidget/backend_banners.rs
index 757d2f9ff9..e769319de7 100644
--- a/codex-rs/tui/src/chatwidget/backend_banners.rs
+++ b/codex-rs/tui/src/chatwidget/backend_banners.rs
@@ -376,9 +376,11 @@ impl ChatWidget {
     }
 
     fn observe_backend_banner_view(&mut self) {
-        let (shown, dismissed) = self.bottom_pane.inline_banner_lifecycle();
-        self.backend_banner_state.shown |= shown;
-        self.backend_banner_state.dismissed |= dismissed;
+        if self.backend_banner_state.presented.is_some() {
+            let (shown, dismissed) = self.bottom_pane.inline_banner_lifecycle();
+            self.backend_banner_state.shown |= shown;
+            self.backend_banner_state.dismissed |= dismissed;
+        }
         self.backend_banner_state.dismissed |= self
             .backend_banner_state
             .picker_dismissed
@@ -441,6 +443,7 @@ impl ChatWidget {
         }
         self.bottom_pane
             .dismiss_view_by_id(LUNA_RESERVE_RECOVERY_VIEW_ID);
+        self.clear_security_setup_banner();
         match (is_reserve, content) {
             (true, Some(content)) => {
                 self.bottom_pane.set_inline_banner(/*banner*/ None);
@@ -510,6 +513,7 @@ impl ChatWidget {
     }
 
     pub(crate) fn clear_backend_banner(&mut self) {
+        self.clear_security_setup_banner();
         self.backend_banner_state = BackendBannerState::default();
         self.backend_banner_notice_model = None;
         self.bottom_pane
diff --git a/codex-rs/tui/src/chatwidget/constructor.rs b/codex-rs/tui/src/chatwidget/constructor.rs
index fb4575ab0d..755da1e626 100644
--- a/codex-rs/tui/src/chatwidget/constructor.rs
+++ b/codex-rs/tui/src/chatwidget/constructor.rs
@@ -164,6 +164,10 @@ impl ChatWidget {
             clock_format: crate::clock_format::ClockFormat::system(),
             usage_notice_state: usage_notice::UsageNoticeState::default(),
             backend_banner_state: backend_banners::BackendBannerState::default(),
+            security_setup_request_id: uuid::Uuid::new_v4(),
+            security_setup_presented: false,
+            security_setup_identity: None,
+            security_setup_dismissed: false,
             automatic_model_switch_state: backend_banners::AutomaticModelSwitchState::default(),
             backend_banner_notice_model: None,
             luna_reserve_notice_account_id: None,
diff --git a/codex-rs/tui/src/chatwidget/security_setup.rs b/codex-rs/tui/src/chatwidget/security_setup.rs
new file mode 100644
index 0000000000..e001f07e1b
--- /dev/null
+++ b/codex-rs/tui/src/chatwidget/security_setup.rs
@@ -0,0 +1,80 @@
+//! Presents the optional setup reminder without displacing account usage controls.
+//! Dismissal survives banner replacement and account notifications until a different identity is verified.
+use super::ChatWidget;
+use crate::app_event::AppEvent;
+use crate::bottom_pane::ActionableBanner;
+use crate::bottom_pane::SelectionItem;
+use crate::security_setup::Identity;
+use crate::security_setup::Notice;
+
+impl ChatWidget {
+    pub(crate) fn inherit_security_setup(&mut self, previous: &mut Self) {
+        // Startup and thread navigation replace the widget while the request is in flight.
+        // Preserve the occurrence, including its rendered/dismissed state.
+        self.security_setup_request_id = previous.security_setup_request_id;
+        self.security_setup_identity = previous.security_setup_identity.clone();
+        self.security_setup_dismissed = previous.security_setup_dismissed
+            || (previous.security_setup_presented
+                && previous.bottom_pane.inline_banner_lifecycle().1);
+        if previous.security_setup_presented && !self.has_applicable_backend_banner() {
+            self.bottom_pane
+                .transfer_inline_banner_from(&mut previous.bottom_pane);
+            self.security_setup_presented = true;
+            previous.security_setup_presented = false;
+        }
+    }
+
+    pub(crate) fn invalidate_security_setup(&mut self) {
+        // AccountUpdated can announce the same account after reconnect. Hide stale content
+        // and reject pending results, but retain dismissal until we verify the identity.
+        self.security_setup_request_id = uuid::Uuid::new_v4();
+        self.clear_security_setup_banner();
+    }
+
+    pub(super) fn clear_security_setup_banner(&mut self) {
+        // Capture this notice's dismissal before the shared slot is cleared or replaced.
+        // Once another banner owns the slot, its lifecycle must not affect this notice.
+        if self.security_setup_presented {
+            self.security_setup_dismissed |= self.bottom_pane.inline_banner_lifecycle().1;
+            self.bottom_pane.set_inline_banner(/*banner*/ None);
+            self.security_setup_presented = false;
+        }
+    }
+
+    pub(crate) fn show_security_setup(&mut self, identity: Identity, notice: Notice) {
+        if !notice.valid() {
+            return;
+        }
+        if self.security_setup_identity.as_ref() != Some(&identity) {
+            self.invalidate_security_setup();
+            self.security_setup_identity = Some(identity);
+            self.security_setup_dismissed = false;
+        }
+        // Reconnect fetches must preserve the current occurrence, including Esc dismissal.
+        if self.security_setup_presented || self.security_setup_dismissed {
+            return;
+        }
+        tracing::debug!(
+            has_backend_banner = self.has_applicable_backend_banner(),
+            "presenting security setup notice"
+        );
+        if self.has_applicable_backend_banner() {
+            return;
+        }
+        self.security_setup_presented = true;
+        self.bottom_pane.set_inline_banner(Some(ActionableBanner {
+            title: notice.title,
+            description: notice.description,
+            actions: vec![SelectionItem {
+                name: notice.action.label,
+                actions: vec![Box::new(move |tx| {
+                    tx.send(AppEvent::OpenUrlInBrowser {
+                        url: notice.action.url.clone(),
+                    })
+                })],
+                ..Default::default()
+            }],
+            ..Default::default()
+        }));
+    }
+}
diff --git a/codex-rs/tui/src/chatwidget/tests.rs b/codex-rs/tui/src/chatwidget/tests.rs
index 3dabfdc058..6d42ca5e5d 100644
--- a/codex-rs/tui/src/chatwidget/tests.rs
+++ b/codex-rs/tui/src/chatwidget/tests.rs
@@ -321,3 +321,6 @@ mod list_spacing_tests;
 
 #[path = "tests/question_notifications_tests.rs"]
 mod question_notifications_tests;
+
+#[path = "tests/security_setup_tests.rs"]
+mod security_setup_tests;
diff --git a/codex-rs/tui/src/chatwidget/tests/security_setup_tests.rs b/codex-rs/tui/src/chatwidget/tests/security_setup_tests.rs
new file mode 100644
index 0000000000..b6fadbf144
--- /dev/null
+++ b/codex-rs/tui/src/chatwidget/tests/security_setup_tests.rs
@@ -0,0 +1,190 @@
+use super::*;
+use crate::security_setup::Identity;
+use crate::security_setup::Notice;
+use serde_json::json;
+
+fn setup_notice() -> Notice {
+    serde_json::from_value(json!({
+        "title":"Keep using Daybreak mode",
+        "description":"Set up Advanced Account Security with a hardware security key by October 1. Already Persona-verified? Add your key before October 15 to skip re-verification.",
+        "action":{"label":"Set up security","url":"https://chatgpt.com/cyber"}
+    }))
+    .unwrap()
+}
+
+fn setup_identity() -> Identity {
+    Identity {
+        account: "account".into(),
+        user: "user".into(),
+    }
+}
+
+#[tokio::test]
+async fn security_setup_preserves_draft_action_and_dismissal_across_widgets() {
+    let (mut chat, _rx, _ops) = make_chatwidget_manual(Some("test-model-a")).await;
+    chat.show_security_setup(setup_identity(), setup_notice());
+    let rendered = normalize_snapshot_paths(render_bottom_popup(&chat, /*width*/ 70));
+    insta::assert_snapshot!("security_setup_banner", rendered);
+    let (mut replacement, mut events, _ops) = make_chatwidget_manual(Some("test-model-a")).await;
+    chat.app_event_tx
+        .voice_only
+        .store(/*val*/ true, std::sync::atomic::Ordering::Relaxed);
+    replacement.inherit_security_setup(&mut chat);
+    chat = replacement;
+    assert!(render_bottom_popup(&chat, /*width*/ 70).contains("Set up security"));
+    chat.handle_key_event(KeyEvent::new(KeyCode::Char('1'), KeyModifiers::NONE));
+    assert!(
+        matches!(events.try_recv(), Ok(AppEvent::OpenUrlInBrowser { url }) if url == "https://chatgpt.com/cyber")
+    );
+    assert!(render_bottom_popup(&chat, /*width*/ 70).contains("Set up security"));
+    chat.handle_key_event(KeyEvent::new(KeyCode::Esc, KeyModifiers::NONE));
+    assert!(!render_bottom_popup(&chat, /*width*/ 70).contains("Set up security"));
+
+    let (mut replacement, _events, _ops) = make_chatwidget_manual(Some("test-model-a")).await;
+    replacement.inherit_security_setup(&mut chat);
+    replacement.show_security_setup(setup_identity(), setup_notice());
+    assert_eq!(
+        replacement.bottom_pane.inline_banner_lifecycle(),
+        (true, true)
+    );
+    assert!(!render_bottom_popup(&replacement, /*width*/ 70).contains("Set up security"));
+
+    replacement.invalidate_security_setup();
+    replacement.show_security_setup(setup_identity(), setup_notice());
+    assert!(!render_bottom_popup(&replacement, /*width*/ 70).contains("Set up security"));
+
+    // A verified change of account starts a new notice occurrence.
+    replacement.invalidate_security_setup();
+    replacement.show_security_setup(
+        Identity {
+            account: "other-account".into(),
+            ..setup_identity()
+        },
+        setup_notice(),
+    );
+    assert!(render_bottom_popup(&replacement, /*width*/ 70).contains("Set up security"));
+}
+
+#[tokio::test]
+async fn security_setup_dismissal_survives_usage_banner_replacement() {
+    for dismiss_security in [true, false] {
+        let (mut chat, _events, _ops) = make_chatwidget_manual(Some("test-model-a")).await;
+        chat.show_security_setup(setup_identity(), setup_notice());
+        assert!(render_bottom_popup(&chat, /*width*/ 70).contains("Set up security"));
+        if dismiss_security {
+            chat.handle_key_event(KeyEvent::new(KeyCode::Esc, KeyModifiers::NONE));
+        }
+
+        let response = codex_app_server_protocol::GetAccountRateLimitsResponse {
+            ordinary_usage_allowed: None,
+            account_id: Some("account".into()),
+            rate_limit_upsell: Some(json!({
+                "banner_type": "selected_model_limit", "model_slug": "test-model-a",
+                "title": "Selected model usage exhausted", "description": "Switch models.",
+                "presentation": "dismissible", "ctas": [],
+            })),
+            rate_limits: snapshot(/*percent*/ 100.0),
+            rate_limits_by_limit_id: None,
+            rate_limit_reset_credits: None,
+        };
+        chat.update_backend_banner(&response);
+        assert!(
+            render_bottom_popup(&chat, /*width*/ 70).contains("Selected model usage exhausted")
+        );
+        if !dismiss_security {
+            // Dismissing usage must not dismiss the security reminder instead.
+            chat.handle_key_event(KeyEvent::new(KeyCode::Esc, KeyModifiers::NONE));
+        }
+
+        // Account refresh must not read the replacement banner's dismissal state.
+        chat.invalidate_security_setup();
+        chat.clear_backend_banner();
+        chat.show_security_setup(setup_identity(), setup_notice());
+        let rendered = normalize_snapshot_paths(render_bottom_popup(&chat, /*width*/ 70));
+        assert_eq!(rendered.contains("Set up security"), !dismiss_security);
+        if dismiss_security {
+            insta::assert_snapshot!("security_setup_dismissed_after_usage", rendered);
+        }
+
+        let (mut replacement, _events, _ops) = make_chatwidget_manual(Some("test-model-a")).await;
+        replacement.inherit_security_setup(&mut chat);
+        replacement.invalidate_security_setup();
+        replacement.show_security_setup(setup_identity(), setup_notice());
+        assert_eq!(
+            render_bottom_popup(&replacement, /*width*/ 70).contains("Set up security"),
+            !dismiss_security
+        );
+
+        // A fresh CLI run has no inherited dismissal and reminds the same eligible user.
+        let (mut fresh, _events, _ops) = make_chatwidget_manual(Some("test-model-a")).await;
+        fresh.show_security_setup(setup_identity(), setup_notice());
+        assert!(render_bottom_popup(&fresh, /*width*/ 70).contains("Set up security"));
+    }
+}
+
+#[tokio::test]
+async fn security_setup_after_cutoff_wraps_in_narrow_terminal() {
+    let (mut chat, _events, _ops) = make_chatwidget_manual(Some("test-model-a")).await;
+    let mut notice = setup_notice();
+    notice.title = "Set up security for Daybreak mode".into();
+    notice.description = "Set up Advanced Account Security with a hardware security key. Already Persona-verified? Add your key before October 15 to skip re-verification. You can keep using Codex while you finish setup.".into();
+    chat.show_security_setup(setup_identity(), notice);
+    insta::assert_snapshot!(
+        "security_setup_after_cutoff",
+        normalize_snapshot_paths(render_bottom_popup(&chat, /*width*/ 48))
+    );
+}
+
+#[tokio::test]
+async fn security_setup_after_persona_grace_wraps_in_narrow_terminal() {
+    let (mut chat, _events, _ops) = make_chatwidget_manual(Some("test-model-a")).await;
+    let mut notice = setup_notice();
+    notice.title = "Set up security for Daybreak mode".into();
+    notice.description = "Set up Advanced Account Security with a hardware security key. Verify each new hardware security key with Persona. You can keep using Codex while you finish setup.".into();
+    chat.show_security_setup(setup_identity(), notice);
+    insta::assert_snapshot!(
+        "security_setup_after_persona_grace",
+        normalize_snapshot_paths(render_bottom_popup(&chat, /*width*/ 48))
+    );
+}
+
+#[tokio::test]
+async fn security_setup_respects_applicable_backend_banner() {
+    for state in ["visible", "dismissed", "another-model"] {
+        let (mut chat, _events, _ops) = make_chatwidget_manual(Some("test-model-a")).await;
+        let response = codex_app_server_protocol::GetAccountRateLimitsResponse {
+            ordinary_usage_allowed: None,
+            account_id: Some("workspace-a".into()),
+            rate_limit_upsell: Some(json!({
+                "banner_type": "selected_model_limit", "model_slug": "test-model-a",
+                "title": "Selected model usage exhausted", "description": "Switch models.",
+                "presentation": "dismissible", "ctas": [],
+            })),
+            rate_limits: snapshot(/*percent*/ 25.0),
+            rate_limits_by_limit_id: None,
+            rate_limit_reset_credits: None,
+        };
+        chat.update_backend_banner(&response);
+        render_bottom_popup(&chat, /*width*/ 70);
+        match state {
+            "dismissed" => {
+                chat.handle_key_event(KeyEvent::new(KeyCode::Esc, KeyModifiers::NONE));
+            }
+            "another-model" => chat.set_model("test-model-b"),
+            "visible" => {}
+            _ => unreachable!(),
+        }
+        chat.show_security_setup(setup_identity(), setup_notice());
+        assert_eq!(
+            render_bottom_popup(&chat, /*width*/ 70).contains("Set up security"),
+            state != "visible"
+        );
+        if state == "another-model" {
+            chat.handle_key_event(KeyEvent::new(KeyCode::Esc, KeyModifiers::NONE));
+            chat.set_model("test-model-a");
+            assert!(
+                render_bottom_popup(&chat, /*width*/ 70).contains("Selected model usage exhausted")
+            );
+        }
+    }
+}
diff --git a/codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__security_setup_tests__security_setup_after_cutoff.snap b/codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__security_setup_tests__security_setup_after_cutoff.snap
new file mode 100644
index 0000000000..00a6396097
--- /dev/null
+++ b/codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__security_setup_tests__security_setup_after_cutoff.snap
@@ -0,0 +1,20 @@
+---
+source: tui/src/chatwidget/tests/security_setup_tests.rs
+assertion_line: 43
+expression: "normalize_snapshot_paths(render_bottom_popup(&chat, 48))"
+---
+  Set up security for Daybreak mode
+  Set up Advanced Account Security with a
+  hardware security key. Already Persona-
+  verified? Add your key before October 15 to
+  skip re-verification. You can keep using
+  Codex while you finish setup.
+
+› 1. Set up security
+
+  Press a number to choose · esc to dismiss ·
+  type to continue
+
+› Ask Codex to do anything
+
+  test-model-a default · /tmp/project
diff --git a/codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__security_setup_tests__security_setup_after_persona_grace.snap b/codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__security_setup_tests__security_setup_after_persona_grace.snap
new file mode 100644
index 0000000000..849c8a09a3
--- /dev/null
+++ b/codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__security_setup_tests__security_setup_after_persona_grace.snap
@@ -0,0 +1,19 @@
+---
+source: tui/src/chatwidget/tests/security_setup_tests.rs
+assertion_line: 56
+expression: "normalize_snapshot_paths(render_bottom_popup(&chat, 48))"
+---
+  Set up security for Daybreak mode
+  Set up Advanced Account Security with a
+  hardware security key. Verify each new
+  hardware security key with Persona. You can
+  keep using Codex while you finish setup.
+
+› 1. Set up security
+
+  Press a number to choose · esc to dismiss ·
+  type to continue
+
+› Ask Codex to do anything
+
+  test-model-a default · /tmp/project
diff --git a/codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__security_setup_tests__security_setup_banner.snap b/codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__security_setup_tests__security_setup_banner.snap
new file mode 100644
index 0000000000..bff2ed1194
--- /dev/null
+++ b/codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__security_setup_tests__security_setup_banner.snap
@@ -0,0 +1,17 @@
+---
+source: tui/src/chatwidget/tests/security_setup_tests.rs
+assertion_line: 19
+expression: rendered
+---
+  Keep using Daybreak mode
+  Set up Advanced Account Security with a hardware security key by
+  October 1. Already Persona-verified? Add your key before October
+  15 to skip re-verification.
+
+› 1. Set up security
+
+  Press a number to choose · esc to dismiss · type to continue
+
+› Ask Codex to do anything
+
+  test-model-a default · /tmp/project
diff --git a/codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__security_setup_tests__security_setup_dismissed_after_usage.snap b/codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__security_setup_tests__security_setup_dismissed_after_usage.snap
new file mode 100644
index 0000000000..77b7fbd67f
--- /dev/null
+++ b/codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__security_setup_tests__security_setup_dismissed_after_usage.snap
@@ -0,0 +1,7 @@
+---
+source: tui/src/chatwidget/tests/security_setup_tests.rs
+expression: rendered
+---
+› Ask Codex to do anything
+
+  test-model-a default · /tmp/project
diff --git a/codex-rs/tui/src/lib.rs b/codex-rs/tui/src/lib.rs
index 1e04ab8575..41802083c8 100644
--- a/codex-rs/tui/src/lib.rs
+++ b/codex-rs/tui/src/lib.rs
@@ -131,6 +131,7 @@ mod experimental_features;
 mod markdown_copy;
 mod permission_discovery;
 mod pets;
+mod security_setup;
 mod worktree_browser;
 pub use custom_terminal::Terminal;
 mod assistant_directives;
diff --git a/codex-rs/tui/src/security_setup.rs b/codex-rs/tui/src/security_setup.rs
new file mode 100644
index 0000000000..9e48eda944
--- /dev/null
+++ b/codex-rs/tui/src/security_setup.rs
@@ -0,0 +1,164 @@
+//! Optional account-security reminders for the local, ChatGPT-authenticated CLI.
+//! The server owns eligibility, rollout and cutoff copy. Reads never block a turn;
+//! no reminder analytics are sent. Unknown or unavailable state produces no notice.
+
+use crate::app_event::AppEvent;
+use crate::app_event_sender::AppEventSender;
+use crate::app_server_session::AppServerSession;
+use crate::legacy_core::config::Config;
+use codex_app_server_protocol::AuthMode;
+use codex_app_server_protocol::ClientRequest;
+use codex_app_server_protocol::GetAuthStatusParams;
+use codex_app_server_protocol::GetAuthStatusResponse;
+use codex_app_server_protocol::RequestId;
+use codex_http_client::ClientRouteClass;
+use codex_http_client::RouteAwareClientPool;
+use codex_login::CodexAuth;
+use serde::Deserialize;
+use std::time::Duration;
+use uuid::Uuid;
+
+#[derive(Clone, Debug, Deserialize)]
+pub(crate) struct Notice {
+    pub title: String,
+    pub description: String,
+    pub action: Action,
+}
+
+#[derive(Clone, Debug, Deserialize)]
+pub(crate) struct Action {
+    pub label: String,
+    pub url: String,
+}
+
+#[derive(Deserialize)]
+struct Response {
+    notice: Option<Notice>,
+}
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub(crate) struct Identity {
+    pub account: String,
+    pub user: String,
+}
+impl Identity {
+    fn from_auth(auth: &CodexAuth) -> Option<Self> {
+        Some(Self {
+            account: auth.get_account_id()?,
+            user: auth.get_chatgpt_user_id()?,
+        })
+    }
+}
+impl Notice {
+    pub(crate) fn valid(&self) -> bool {
+        !self.title.trim().is_empty()
+            && self.title.len() <= 256
+            && self.description.len() <= 2048
+            && !self.title.chars().any(char::is_control)
+            && !self.description.chars().any(char::is_control)
+            && !self.action.label.trim().is_empty()
+            && self.action.label.len() <= 128
+            && !self.action.label.chars().any(char::is_control)
+            && url::Url::parse(&self.action.url).is_ok_and(|url| {
+                url.scheme() == "https"
+                    && url.host_str() == Some("chatgpt.com")
+                    && url.username().is_empty()
+                    && url.password().is_none()
+                    && url.port().is_none()
+            })
+    }
+}
+
+pub(crate) fn prefetch(
+    config: &Config,
+    server: &AppServerSession,
+    tx: AppEventSender,
+    request_id: Uuid,
+) {
+    if config.model_provider_id != "openai" || server.uses_remote_workspace() {
+        return;
+    }
+    let config = config.clone();
+    let request_handle = server.request_handle();
+    tokio::spawn(async move {
+        let result = tokio::time::timeout(Duration::from_secs(3), async {
+            // Saved credentials must match the connected server, which may use external auth.
+            let status: GetAuthStatusResponse = request_handle
+                .request_typed(ClientRequest::GetAuthStatus {
+                    request_id: RequestId::String(Uuid::new_v4().to_string()),
+                    params: GetAuthStatusParams {
+                        include_token: Some(true),
+                        refresh_token: Some(false),
+                    },
+                })
+                .await
+                .ok()?;
+            let auth = config
+                .auth_config()
+                .load_auth(/*enable_codex_api_key_env*/ false)
+                .await
+                .ok()
+                .flatten()?;
+            if !matches!(auth, CodexAuth::Chatgpt(_)) || auth.is_fedramp_account() {
+                return None;
+            }
+            let saved_token = auth.get_token().ok()?;
+            if status.auth_method != Some(AuthMode::Chatgpt)
+                || status.auth_token.as_deref() != Some(saved_token.as_str())
+            {
+                return None;
+            }
+            let identity = Identity::from_auth(&auth)?;
+            let client = RouteAwareClientPool::new_without_redirects(
+                config.http_client_factory(),
+                ClientRouteClass::Api,
+            );
+            let response = client
+                .get(format!(
+                    "{}/wham/security-setup",
+                    config.chatgpt_base_url.trim_end_matches('/')
+                ))
+                .headers(codex_model_provider::auth_provider_from_auth(&auth).to_auth_headers())
+                .header(
+                    "User-Agent",
+                    codex_login::default_client::get_codex_user_agent(),
+                )
+                .send()
+                .await
+                .ok()?;
+            if !response.status().is_success() {
+                return None;
+            }
+            let notice = response.json::<Response>().await.ok()?.notice?;
+            tracing::debug!(valid = notice.valid(), "received security setup notice");
+            if !notice.valid() {
+                return None;
+            }
+            let current = config
+                .auth_config()
+                .load_auth(/*enable_codex_api_key_env*/ false)
+                .await
+                .ok()
+                .flatten()?;
+            if Identity::from_auth(&current).as_ref() != Some(&identity) {
+                tracing::debug!("security setup identity changed during fetch");
+                return None;
+            }
+            Some((identity, notice))
+        })
+        .await
+        .ok()
+        .flatten();
+        if let Some((identity, notice)) = result {
+            tracing::debug!("security setup notice ready");
+            tx.send(AppEvent::SecuritySetupLoaded {
+                request_id,
+                identity,
+                notice,
+            });
+        }
+    });
+}
+
+#[cfg(test)]
+#[path = "security_setup_tests.rs"]
+mod tests;
diff --git a/codex-rs/tui/src/security_setup_tests.rs b/codex-rs/tui/src/security_setup_tests.rs
new file mode 100644
index 0000000000..701bd4a5e0
--- /dev/null
+++ b/codex-rs/tui/src/security_setup_tests.rs
@@ -0,0 +1,29 @@
+use super::*;
+use pretty_assertions::assert_eq;
+use serde_json::json;
+
+#[test]
+fn security_setup_rejects_unsafe_actions_and_terminal_controls() {
+    let value = json!({"title":"Keep using Daybreak mode","description":"Set up security.",
+        "action":{"label":"Set up security","url":"https://chatgpt.com/cyber"}});
+    let notice: Notice = serde_json::from_value(value.clone()).unwrap();
+    assert!(notice.valid());
+    for url in [
+        "http://chatgpt.com/cyber",
+        "https://chatgpt.com.evil.test/cyber",
+        "https://evil.test/",
+        "https://user@chatgpt.com/cyber",
+        "https://chatgpt.com:8080/cyber",
+        "javascript:alert(1)",
+    ] {
+        let mut invalid = value.clone();
+        invalid["action"]["url"] = json!(url);
+        assert!(
+            !serde_json::from_value::<Notice>(invalid).unwrap().valid(),
+            "{url}"
+        );
+    }
+    let mut invalid = notice;
+    invalid.title = "untrusted\u{1b}[31m".into();
+    assert_eq!(invalid.valid(), false);
+}