diff --git a/src/corelib/time/qtimezone.cpp b/src/corelib/time/qtimezone.cpp
index 7dd5dbf4234..8ce967cf9fc 100644
--- a/src/corelib/time/qtimezone.cpp
+++ b/src/corelib/time/qtimezone.cpp
@@ -829,6 +829,34 @@ QByteArray QTimeZone::id() const
     return QByteArray();
 }
 
+/*!
+    \since 6.8
+    Returns \c true if \a alias is an alternative name for this timezone.
+
+    The IANA (formerly Olson) database has renamed some zones during its
+    history. There are also some zones that only differed prior to 1970 but are
+    now treated as synonymous. Some backends may have data reaching to before
+    1970 and produce distinct zones in the latter case. Others may produce zones
+    indistinguishable except by id(). This method determines whether an ID
+    refers (at least since 1970) to the same zone that this timezone object
+    describes.
+
+    This method is only available when feature \c timezone is enabled.
+*/
+bool QTimeZone::aliasMatches(QByteArrayView alias) const
+{
+    if (alias == id())
+        return true;
+    QByteArray mine = QTimeZonePrivate::aliasToIana(id());
+    // Empty if id() aliases to itself, which we've already checked:
+    if (!mine.isEmpty() && alias == mine)
+        return true;
+    QByteArray its = QTimeZonePrivate::aliasToIana(alias);
+    // Empty if alias aliases to itself, which we've already compared to id()
+    // and, where relevant, mine.
+    return !its.isEmpty() && its == (mine.isEmpty() ? id() : mine);
+}
+
 /*!
     \since 6.2
 
diff --git a/src/corelib/time/qtimezone.h b/src/corelib/time/qtimezone.h
index 46c7d6312b8..6c490c4e252 100644
--- a/src/corelib/time/qtimezone.h
+++ b/src/corelib/time/qtimezone.h
@@ -166,6 +166,7 @@ public:
     };
     typedef QList<OffsetData> OffsetDataList;
 
+    bool aliasMatches(QByteArrayView alias) const;
     QByteArray id() const;
     QLocale::Territory territory() const;
 #  if QT_DEPRECATED_SINCE(6, 6)
diff --git a/src/corelib/time/qtimezoneprivate.cpp b/src/corelib/time/qtimezoneprivate.cpp
index 4c01d095c4a..1b70f6385f0 100644
--- a/src/corelib/time/qtimezoneprivate.cpp
+++ b/src/corelib/time/qtimezoneprivate.cpp
@@ -780,6 +780,9 @@ QByteArray QTimeZonePrivate::aliasToIana(QByteArrayView alias)
                                        alias, earlierAliasId);
     if (data != std::end(aliasMappingTable) && data->aliasId() == alias)
         return data->ianaId().toByteArray();
+    // Note: empty return means not an alias, which is true of an ID that others
+    // are aliases to, as the table omits self-alias entries. Let caller sort
+    // that out, rather than allocating to return alias.toByteArray().
     return {};
 }
 
diff --git a/tests/auto/corelib/time/qtimezone/tst_qtimezone.cpp b/tests/auto/corelib/time/qtimezone/tst_qtimezone.cpp
index 19c3119df58..f30286e5e7c 100644
--- a/tests/auto/corelib/time/qtimezone/tst_qtimezone.cpp
+++ b/tests/auto/corelib/time/qtimezone/tst_qtimezone.cpp
@@ -7,6 +7,7 @@
 #include <private/qcomparisontesthelper_p.h>
 
 #include <qlocale.h>
+#include <qscopeguard.h>
 
 #if defined(Q_OS_WIN)
 #include <QOperatingSystemVersion>
@@ -16,6 +17,8 @@
 #  define USING_WIN_TZ
 #endif
 
+using namespace Qt::StringLiterals;
+
 class tst_QTimeZone : public QObject
 {
     Q_OBJECT
@@ -38,6 +41,8 @@ private Q_SLOTS:
     void availableTimeZoneIds();
     void utcOffsetId_data();
     void utcOffsetId();
+    void aliasMatches_data();
+    void aliasMatches();
     void specificTransition_data();
     void specificTransition();
     void transitionEachZone_data();
@@ -558,9 +563,12 @@ void tst_QTimeZone::isTimeZoneIdAvailable()
     const QList<QByteArray> available = QTimeZone::availableTimeZoneIds();
     for (const QByteArray &id : available) {
         QVERIFY2(QTimeZone::isTimeZoneIdAvailable(id), id);
-        QVERIFY2(QTimeZone(id).isValid(), id);
-        QCOMPARE(QTimeZone(id).id(), id);
+        const QTimeZone zone(id);
+        QVERIFY2(zone.isValid(), id);
+        QVERIFY2(zone.aliasMatches(id), zone.id() + " != " + id);
     }
+    // availableTimeZoneIds() doesn't list all possible offset IDs, but
+    // isTimeZoneIdAvailable() should accept them.
     for (qint32 offset = QTimeZone::MinUtcOffsetSecs;
          offset <= QTimeZone::MinUtcOffsetSecs; ++offset) {
         const QByteArray id = QTimeZone(offset).id();
@@ -700,6 +708,61 @@ void tst_QTimeZone::utcOffsetId()
     }
 }
 
+void tst_QTimeZone::aliasMatches_data()
+{
+    QTest::addColumn<QByteArray>("iana");
+    QTest::addColumn<QByteArray>("alias");
+
+    QTest::newRow("Montreal=Toronto") << "America/Toronto"_ba << "America/Montreal"_ba;
+    QTest::newRow("Asmera=Asmara") << "Africa/Asmara"_ba << "Africa/Asmera"_ba;
+    QTest::newRow("Argentina/Catamarca")
+        << "America/Argentina/Catamarca"_ba << "America/Catamarca"_ba;
+    QTest::newRow("Godthab=Nuuk") << "America/Nuuk"_ba << "America/Godthab"_ba;
+    QTest::newRow("Indiana/Indianapolis")
+        << "America/Indiana/Indianapolis"_ba << "America/Indianapolis"_ba;
+    QTest::newRow("Kentucky/Louisville")
+        << "America/Kentucky/Louisville"_ba << "America/Louisville"_ba;
+    QTest::newRow("Calcutta=Kolkata") << "Asia/Kolkata"_ba << "Asia/Calcutta"_ba;
+    QTest::newRow("Katmandu=Kathmandu") << "Asia/Kathmandu"_ba << "Asia/Katmandu"_ba;
+    QTest::newRow("Rangoon=Yangon") << "Asia/Yangon"_ba << "Asia/Rangoon"_ba;
+    QTest::newRow("Saigon=Ho_Chi_Minh") << "Asia/Ho_Chi_Minh"_ba << "Asia/Saigon"_ba;
+    QTest::newRow("Faeroe=Faroe") << "Atlantic/Faroe"_ba << "Atlantic/Faeroe"_ba;
+    QTest::newRow("Currie=Hobart") << "Australia/Hobart"_ba << "Australia/Currie"_ba;
+    QTest::newRow("Kiev=Kyiv") << "Europe/Kyiv"_ba << "Europe/Kiev"_ba;
+    QTest::newRow("Uzhgorod=Kyiv") << "Europe/Kyiv"_ba << "Europe/Uzhgorod"_ba;
+    QTest::newRow("Zaporozhye=Kyiv") << "Europe/Kyiv"_ba << "Europe/Zaporozhye"_ba;
+    QTest::newRow("Fiji=Fiji") << "Pacific/Fiji"_ba << "Pacific/Fiji"_ba;
+    QTest::newRow("Enderbury=Enderbury") << "Pacific/Enderbury"_ba << "Pacific/Enderbury"_ba;
+}
+
+void tst_QTimeZone::aliasMatches()
+{
+    QFETCH(const QByteArray, iana);
+    QFETCH(const QByteArray, alias);
+    const QTimeZone zone(iana);
+    const QTimeZone peer(alias);
+    if (!zone.isValid())
+        QSKIP("Backend doesn't support IANA ID");
+
+    auto report = qScopeGuard([zone, peer]() {
+        const QByteArray zid = zone.id(), pid = peer.id();
+        qDebug("Using %s and %s", zid.constData(), pid.constData());
+    });
+    QVERIFY2(peer.isValid(), "Construction should have fallen back on IANA ID");
+    QVERIFY(zone.aliasMatches(zone.id()));
+    QVERIFY(zone.aliasMatches(iana));
+    QVERIFY(peer.aliasMatches(peer.id()));
+    QVERIFY(peer.aliasMatches(alias));
+    QEXPECT_FAIL("Currie=Hobart", "Needs update to CLDR v44.1", Abort);
+    QEXPECT_FAIL("Uzhgorod=Kyiv", "Needs update to CLDR v44.1", Abort);
+    QEXPECT_FAIL("Zaporozhye=Kyiv", "Needs update to CLDR v44.1", Abort);
+    QVERIFY(zone.aliasMatches(peer.id()));
+    QVERIFY(zone.aliasMatches(alias));
+    QVERIFY(peer.aliasMatches(zone.id()));
+    QVERIFY(peer.aliasMatches(iana));
+    report.dismiss();
+}
+
 void tst_QTimeZone::specificTransition_data()
 {
     QTest::addColumn<QByteArray>("zone");
@@ -924,7 +987,7 @@ void tst_QTimeZone::stressTest()
     for (const QByteArray &id : idList) {
         QTimeZone testZone = QTimeZone(id);
         QCOMPARE(testZone.isValid(), true);
-        QCOMPARE(testZone.id(), id);
+        QVERIFY2(testZone.aliasMatches(id), testZone.id() + " != " + id);
         QDateTime testDate = QDateTime(QDate(2015, 1, 1), QTime(0, 0), UTC);
         testZone.territory();
         testZone.comment();
@@ -1860,7 +1923,7 @@ void tst_QTimeZone::stdCompatibility()
     QByteArrayView zoneName = QByteArrayView(timeZone->name());
     QTimeZone tz = QTimeZone::fromStdTimeZonePtr(timeZone);
     if (tz.isValid())
-        QCOMPARE(tz.id(), zoneName);
+        QVERIFY2(tz.aliasMatches(zoneName), tz.id().constData());
     else
         QVERIFY(!QTimeZone::isTimeZoneIdAvailable(zoneName.toByteArray()));
 #else