diff --git a/bundles/org.eclipse.ui.forms/src/org/eclipse/ui/forms/widgets/ExpandableComposite.java b/bundles/org.eclipse.ui.forms/src/org/eclipse/ui/forms/widgets/ExpandableComposite.java
index 7c38314844f..f2ca24a22bc 100644
--- a/bundles/org.eclipse.ui.forms/src/org/eclipse/ui/forms/widgets/ExpandableComposite.java
+++ b/bundles/org.eclipse.ui.forms/src/org/eclipse/ui/forms/widgets/ExpandableComposite.java
@@ -22,6 +22,7 @@
 
 import org.eclipse.core.runtime.Assert;
 import org.eclipse.core.runtime.ListenerList;
+import org.eclipse.core.runtime.Platform.OS;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.FocusEvent;
 import org.eclipse.swt.events.FocusListener;
@@ -287,7 +288,13 @@ protected void layout(Composite parent, boolean changed) {
 			Point labelDefault = this.textLabelCache.computeSize(SWT.DEFAULT, SWT.DEFAULT);
 
 			int tcWidthBeforeSplit = Math.min(width, tcDefault.x);
-			int labelWidthBeforeSplit = Math.min(width, labelDefault.x);
+
+			int additionalLabelWidthPadding = 0;
+			if (OS.isWindows()) {
+				/* compensate rounding issue in windows */
+				additionalLabelWidthPadding = 1;
+			}
+			int labelWidthBeforeSplit = Math.min(width, labelDefault.x + additionalLabelWidthPadding);
 
 			int tcWidthAfterSplit = tcWidthBeforeSplit;
 			int labelWidthAfterSplit = labelWidthBeforeSplit;