diff --git a/src/plugins/texteditor/tabsettings.cpp b/src/plugins/texteditor/tabsettings.cpp
index f87ab2ac8cf27efb0fb792aa948234b3609c3a88..19145a7cd9748d6e3860db950719fda621c7d8dd 100644
--- a/src/plugins/texteditor/tabsettings.cpp
+++ b/src/plugins/texteditor/tabsettings.cpp
@@ -132,7 +132,7 @@ bool TabSettings::isIndentationClean(const QString &text) const
 
         if (c == QLatin1Char(' ')) {
             ++spaceCount;
-            if (spaceCount == m_tabSize)
+            if (!m_spacesForTabs && spaceCount == m_tabSize)
                 return false;
         } else if (c == QLatin1Char('\t')) {
             if (m_spacesForTabs || spaceCount != m_indentSize)