diff --git a/src/corelib/text/qbytearray.cpp b/src/corelib/text/qbytearray.cpp
index 7795fd7f11..5bb63bbbb2 100644
--- a/src/corelib/text/qbytearray.cpp
+++ b/src/corelib/text/qbytearray.cpp
@@ -1821,26 +1821,6 @@ void QByteArray::expand(qsizetype i)
     resize(qMax(i + 1, size()));
 }
 
-/*!
-   \internal
-   Return a QByteArray that is sure to be '\\0'-terminated.
-
-   By default, all QByteArray have an extra NUL at the end,
-   guaranteeing that assumption. However, if QByteArray::fromRawData
-   is used, then the NUL is there only if the user put it there. We
-   can't be sure.
-*/
-QByteArray QByteArray::nulTerminated() const
-{
-    // is this fromRawData?
-    if (d.isMutable())
-        return *this;           // no, then we're sure we're zero terminated
-
-    QByteArray copy(*this);
-    copy.detach();
-    return copy;
-}
-
 /*!
     \fn QByteArray &QByteArray::prepend(QByteArrayView ba)
 
diff --git a/src/corelib/text/qbytearray.h b/src/corelib/text/qbytearray.h
index 5a6dc354ba..f3c167d217 100644
--- a/src/corelib/text/qbytearray.h
+++ b/src/corelib/text/qbytearray.h
@@ -1,6 +1,6 @@
 /****************************************************************************
 **
-** Copyright (C) 2020 The Qt Company Ltd.
+** Copyright (C) 2022 The Qt Company Ltd.
 ** Copyright (C) 2016 Intel Corporation.
 ** Contact: https://www.qt.io/licensing/
 **
@@ -485,7 +485,6 @@ private:
     void reallocData(qsizetype alloc, QArrayData::AllocationOption option);
     void reallocGrowData(qsizetype n);
     void expand(qsizetype i);
-    QByteArray nulTerminated() const;
 
     static QByteArray toLower_helper(const QByteArray &a);
     static QByteArray toLower_helper(QByteArray &a);