diff --git a/src/server/surface_interface.h b/src/server/surface_interface.h
--- a/src/server/surface_interface.h
+++ b/src/server/surface_interface.h
@@ -112,6 +112,14 @@
      * @since 5.3
      **/
     QSize size() const;
+    /**
+     * Returns the rectangle that bounds this surface and all of its sub-surfaces.
+     *
+     * QPoint(0, 0) corresponds to the upper left corner of this surface.
+     *
+     * @since 5.69
+     */
+    QRect boundingRect() const;
 
     /**
      * @returns The SubSurface for this Surface in case there is one.
diff --git a/src/server/surface_interface.cpp b/src/server/surface_interface.cpp
--- a/src/server/surface_interface.cpp
+++ b/src/server/surface_interface.cpp
@@ -772,6 +772,19 @@
     return QSize();
 }
 
+QRect SurfaceInterface::boundingRect() const
+{
+    QRect rect(QPoint(0, 0), size());
+
+    const QList<QPointer<SubSurfaceInterface>> subSurfaces = childSubSurfaces();
+    for (const SubSurfaceInterface *subSurface : subSurfaces) {
+        const SurfaceInterface *childSurface = subSurface->surface();
+        rect |= childSurface->boundingRect().translated(subSurface->position());
+    }
+
+    return rect;
+}
+
 QPointer< ShadowInterface > SurfaceInterface::shadow() const
 {
     Q_D();