diff --git a/effects/backgroundcontrast/contrast.h b/effects/backgroundcontrast/contrast.h
--- a/effects/backgroundcontrast/contrast.h
+++ b/effects/backgroundcontrast/contrast.h
@@ -56,6 +56,7 @@
     void paintEffectFrame(EffectFrame *frame, const QRegion &region, double opacity, double frameOpacity) override;
 
     bool provides(Feature feature) override;
+    bool isActive() const override;
 
     int requestedEffectChainPosition() const override {
         return 76;
diff --git a/effects/backgroundcontrast/contrast.cpp b/effects/backgroundcontrast/contrast.cpp
--- a/effects/backgroundcontrast/contrast.cpp
+++ b/effects/backgroundcontrast/contrast.cpp
@@ -525,5 +525,10 @@
     shader->unbind();
 }
 
+bool ContrastEffect::isActive() const
+{
+    return !effects->isScreenLocked();
+}
+
 } // namespace KWin
 
diff --git a/effects/blur/blur.h b/effects/blur/blur.h
--- a/effects/blur/blur.h
+++ b/effects/blur/blur.h
@@ -59,6 +59,7 @@
     void paintEffectFrame(EffectFrame *frame, const QRegion &region, double opacity, double frameOpacity) override;
 
     bool provides(Feature feature) override;
+    bool isActive() const override;
 
     int requestedEffectChainPosition() const override {
         return 75;
diff --git a/effects/blur/blur.cpp b/effects/blur/blur.cpp
--- a/effects/blur/blur.cpp
+++ b/effects/blur/blur.cpp
@@ -831,5 +831,10 @@
     m_shader->unbind();
 }
 
+bool BlurEffect::isActive() const
+{
+    return !effects->isScreenLocked();
+}
+
 } // namespace KWin