diff --git a/src/widgets/widgets/qstackedwidget.cpp b/src/widgets/widgets/qstackedwidget.cpp
index a565d4ab4cc..9a9d2ddcbd1 100644
--- a/src/widgets/widgets/qstackedwidget.cpp
+++ b/src/widgets/widgets/qstackedwidget.cpp
@@ -254,7 +254,7 @@ void QStackedWidget::setCurrentWidget(QWidget *widget)
 
     \sa currentIndex(), widget()
 */
-int QStackedWidget::indexOf(QWidget *widget) const
+int QStackedWidget::indexOf(const QWidget *widget) const
 {
     return d_func()->layout->indexOf(widget);
 }
diff --git a/src/widgets/widgets/qstackedwidget.h b/src/widgets/widgets/qstackedwidget.h
index 5508f905d46..5ca6429d758 100644
--- a/src/widgets/widgets/qstackedwidget.h
+++ b/src/widgets/widgets/qstackedwidget.h
@@ -66,7 +66,7 @@ public:
     QWidget *currentWidget() const;
     int currentIndex() const;
 
-    int indexOf(QWidget *) const;
+    int indexOf(const QWidget *) const;
     QWidget *widget(int) const;
     int count() const;
 
diff --git a/src/widgets/widgets/qtabwidget.cpp b/src/widgets/widgets/qtabwidget.cpp
index 35b097b0c72..3c2bc4f66b3 100644
--- a/src/widgets/widgets/qtabwidget.cpp
+++ b/src/widgets/widgets/qtabwidget.cpp
@@ -719,7 +719,7 @@ void QTabWidget::setCurrentIndex(int index)
     Returns the index position of the page occupied by the widget \a
     w, or -1 if the widget cannot be found.
 */
-int QTabWidget::indexOf(QWidget* w) const
+int QTabWidget::indexOf(const QWidget *w) const
 {
     Q_D(const QTabWidget);
     return d->stack->indexOf(w);
diff --git a/src/widgets/widgets/qtabwidget.h b/src/widgets/widgets/qtabwidget.h
index 0b91f077e02..7de02d3b7eb 100644
--- a/src/widgets/widgets/qtabwidget.h
+++ b/src/widgets/widgets/qtabwidget.h
@@ -104,7 +104,7 @@ public:
     int currentIndex() const;
     QWidget *currentWidget() const;
     QWidget *widget(int index) const;
-    int indexOf(QWidget *widget) const;
+    int indexOf(const QWidget *widget) const;
     int count() const;
 
     enum TabPosition { North, South, West, East };
diff --git a/src/widgets/widgets/qtoolbox.cpp b/src/widgets/widgets/qtoolbox.cpp
index 9adf8fcd053..acd306b7f6b 100644
--- a/src/widgets/widgets/qtoolbox.cpp
+++ b/src/widgets/widgets/qtoolbox.cpp
@@ -560,7 +560,7 @@ QWidget *QToolBox::widget(int index) const
     exist.
 */
 
-int QToolBox::indexOf(QWidget *widget) const
+int QToolBox::indexOf(const QWidget *widget) const
 {
     Q_D(const QToolBox);
     const QToolBoxPrivate::Page *c = (widget ? d->page(widget) : nullptr);
diff --git a/src/widgets/widgets/qtoolbox.h b/src/widgets/widgets/qtoolbox.h
index d12d4dcfeca..e572c7835a6 100644
--- a/src/widgets/widgets/qtoolbox.h
+++ b/src/widgets/widgets/qtoolbox.h
@@ -84,7 +84,7 @@ public:
     int currentIndex() const;
     QWidget *currentWidget() const;
     QWidget *widget(int index) const;
-    int indexOf(QWidget *widget) const;
+    int indexOf(const QWidget *widget) const;
     int count() const;
 
 public Q_SLOTS: