diff --git a/src/corelib/text/qlocale.cpp b/src/corelib/text/qlocale.cpp
index 09226e97992..48996eaacbb 100644
--- a/src/corelib/text/qlocale.cpp
+++ b/src/corelib/text/qlocale.cpp
@@ -770,6 +770,16 @@ static QLocalePrivate *c_private() noexcept
     return &c_locale;
 }
 
+static constexpr QLocale::NumberOptions defaultNumberOptions(QLocale::Language forLanguage)
+{
+    return forLanguage == QLocale::C ? QLocale::OmitGroupSeparator : QLocale::DefaultNumberOptions;
+}
+
+static constexpr QLocale::NumberOptions defaultNumberOptions(quint16 forLanguage)
+{
+    return defaultNumberOptions(QLocale::Language(forLanguage));
+}
+
 #ifndef QT_NO_SYSTEMLOCALE
 /******************************************************************************
 ** Default system locale behavior
@@ -954,7 +964,8 @@ QDataStream &operator>>(QDataStream &ds, QLocale &l)
 #endif // QT_NO_DATASTREAM
 
 Q_GLOBAL_STATIC(QSharedDataPointer<QLocalePrivate>, defaultLocalePrivate,
-                new QLocalePrivate(defaultData(), defaultIndex()))
+                new QLocalePrivate(defaultData(), defaultIndex(),
+                                   defaultNumberOptions(defaultData()->m_language_id)))
 
 static QLocalePrivate *localePrivateByName(QStringView name)
 {
@@ -963,8 +974,7 @@ static QLocalePrivate *localePrivateByName(QStringView name)
     const qsizetype index = QLocaleData::findLocaleIndex(QLocaleId::fromName(name));
     Q_ASSERT(index >= 0 && index < locale_data_size);
     return new QLocalePrivate(locale_data + index, index,
-                              locale_data[index].m_language_id == QLocale::C
-                              ? QLocale::OmitGroupSeparator : QLocale::DefaultNumberOptions);
+                              defaultNumberOptions(locale_data[index].m_language_id));
 }
 
 static QLocalePrivate *findLocalePrivate(QLocale::Language language, QLocale::Script script,
@@ -2971,6 +2981,7 @@ QLocale QLocale::system()
     // to ensure that locale's index stays up to date:
     systemData(&locale.m_index);
     Q_ASSERT(locale.m_index >= 0 && locale.m_index < locale_data_size);
+    locale.m_numberOptions = defaultNumberOptions(locale.m_data->m_language_id);
 
     return QLocale(locale);
 }
diff --git a/tests/auto/corelib/text/qlocale/tst_qlocale.cpp b/tests/auto/corelib/text/qlocale/tst_qlocale.cpp
index 2c13af1f4a1..d421aecb6b8 100644
--- a/tests/auto/corelib/text/qlocale/tst_qlocale.cpp
+++ b/tests/auto/corelib/text/qlocale/tst_qlocale.cpp
@@ -4232,17 +4232,22 @@ void tst_QLocale::mySystemLocale()
     QFETCH(QLocale::Language, language);
     QFETCH(QStringList, uiLanguages);
 
+    const QLocale::NumberOptions eno
+        = language == QLocale::C ? QLocale::OmitGroupSeparator : QLocale::DefaultNumberOptions;
+
     {
         MySystemLocale sLocale(name);
         QCOMPARE(QLocale().language(), language);
-        QCOMPARE(QLocale::system().language(), language);
+        const QLocale sys = QLocale::system();
+        QCOMPARE(sys.language(), language);
         auto reporter = qScopeGuard([]() {
             qDebug("Actual entries:\n\t%s",
                    qPrintable(QLocale::system().uiLanguages().join(u"\n\t")));
         });
-        QCOMPARE(QLocale::system().uiLanguages(), uiLanguages);
-        QCOMPARE(QLocale::system().uiLanguages(QLocale::TagSeparator::Underscore),
+        QCOMPARE(sys.uiLanguages(), uiLanguages);
+        QCOMPARE(sys.uiLanguages(QLocale::TagSeparator::Underscore),
                  uiLanguages.replaceInStrings(u"-", u"_"));
+        QCOMPARE(sys.numberOptions(), eno);
         reporter.dismiss();
     }