diff --git a/greeter/CMakeLists.txt b/greeter/CMakeLists.txt
--- a/greeter/CMakeLists.txt
+++ b/greeter/CMakeLists.txt
@@ -29,6 +29,12 @@
     BASENAME ksld
 )
 
+set(login1_manager_xml dbus/org.freedesktop.login1.Manager.xml)
+qt5_add_dbus_interface(kscreenlocker_greet_SRCS
+    ${login1_manager_xml}
+    login1_interface
+)
+
 add_executable(kscreenlocker_greet ${kscreenlocker_greet_SRCS})
 
 target_link_libraries(kscreenlocker_greet
@@ -40,6 +46,7 @@
                         KF5::QuickAddons
                         KF5::WindowSystem
                         Qt5::Quick
+                        Qt5::DBus
                         Qt5::Qml
                         Qt5::X11Extras
                         ${X11_LIBRARIES}
diff --git a/greeter/authenticator.h b/greeter/authenticator.h
--- a/greeter/authenticator.h
+++ b/greeter/authenticator.h
@@ -48,6 +48,7 @@
     void failed();
     void succeeded();
     void graceLockedChanged();
+    void suspend() const;
     void message(const QString & msg); // don't remove the "msg" param, used in QML!!!
     void error(const QString & err); // don't remove the "err" param, used in QML!!!
 
diff --git a/greeter/dbus/org.freedesktop.login1.Manager.xml b/greeter/dbus/org.freedesktop.login1.Manager.xml
new file mode 100644
--- /dev/null
+++ b/greeter/dbus/org.freedesktop.login1.Manager.xml
@@ -0,0 +1,9 @@
+<!DOCTYPE node PUBLIC "-//freedesktop//DTD D-BUS Object Introspection 1.0//EN"
+"http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd">
+<node>
+ <interface name="org.freedesktop.login1.Manager">
+  <signal name="PrepareForSleep">
+   <arg name="start" type="b"/>
+  </signal>
+ </interface>
+</node>
diff --git a/greeter/fallbacktheme/Greeter.qml b/greeter/fallbacktheme/Greeter.qml
--- a/greeter/fallbacktheme/Greeter.qml
+++ b/greeter/fallbacktheme/Greeter.qml
@@ -162,5 +162,8 @@
         onError: function(text) {
             root.notification = text;
         }
+        onSuspend: {
+            password.clear();
+        }
     }
 }
diff --git a/greeter/greeterapp.h b/greeter/greeterapp.h
--- a/greeter/greeterapp.h
+++ b/greeter/greeterapp.h
@@ -72,6 +72,7 @@
 
 public Q_SLOTS:
     void desktopResized();
+    void onPrepareForSleep(bool start);
 
 protected:
     bool eventFilter(QObject *obj, QEvent *event) override;
diff --git a/greeter/greeterapp.cpp b/greeter/greeterapp.cpp
--- a/greeter/greeterapp.cpp
+++ b/greeter/greeterapp.cpp
@@ -24,6 +24,7 @@
 #include "noaccessnetworkaccessmanagerfactory.h"
 #include "wallpaper_integration.h"
 #include "lnf_integration.h"
+#include "login1_interface.h"
 
 #include <config-kscreenlocker.h>
 
@@ -54,6 +55,7 @@
 #include <qscreen.h>
 #include <QThread>
 #include <QMimeData>
+#include <QDBusConnection>
 
 #include <QQuickView>
 #include <QQuickItem>
@@ -133,6 +135,20 @@
     if (QX11Info::isPlatformX11()) {
         installNativeEventFilter(new FocusOutEventFilter);
     }
+
+    QDBusConnection::systemBus().connect(QStringLiteral("org.freedesktop.login1"),
+                                         QStringLiteral("/org/freedesktop/login1"),
+                                         QStringLiteral("org.freedesktop.login1.Manager"),
+                                         QStringLiteral("PrepareForSleep"),
+                                         this,
+                                         SLOT(onPrepareForSleep(bool)));
+}
+
+void UnlockApp::onPrepareForSleep(bool start) {
+    if (start) {
+        // start of sleep, aka suspend
+        emit m_authenticator->suspend();
+    }
 }
 
 UnlockApp::~UnlockApp()