diff --git a/autotests/src/scripting_test.cpp b/autotests/src/scripting_test.cpp
--- a/autotests/src/scripting_test.cpp
+++ b/autotests/src/scripting_test.cpp
@@ -38,7 +38,6 @@
 #include <QtCore/QFile>
 #include <QtCore/QDir>
 #include <QtCore/QString>
-#include <QtCore/QRegExp>
 #include <QtCore/QTextStream>
 #include <QtCore/QList>
 #include <QtCore/QTimer>
diff --git a/src/completion/katewordcompletion.cpp b/src/completion/katewordcompletion.cpp
--- a/src/completion/katewordcompletion.cpp
+++ b/src/completion/katewordcompletion.cpp
@@ -41,7 +41,7 @@
 #include <KConfigGroup>
 #include <KAboutData>
 
-#include <QRegExp>
+#include <QRegularExpression>
 #include <QSet>
 #include <QString>
 #include <QAction>
@@ -313,7 +313,7 @@
     KTextEditor::MovingRange *liRange;       // range containing last inserted text
     KTextEditor::Range dcRange;  // current range to be completed by directional completion
     KTextEditor::Cursor dcCursor;     // directional completion search cursor
-    QRegExp re;           // hrm
+    QRegularExpression re;           // hrm
     int directionalPos;   // be able to insert "" at the correct time
     bool isCompleting; // true when the directional completion is doing a completion
 };
@@ -469,13 +469,13 @@
 
     while (true) {
         //qCDebug(LOG_KTE)<<"SEARCHING FOR "<<d->re.pattern()<<" "<<ln<<" at "<<d->dcCursor;
-        pos = fw ?
-              d->re.indexIn(ln, d->dcCursor.column()) :
-              d->re.lastIndexIn(ln, d->dcCursor.column());
+        QRegularExpressionMatch match;
+        pos = fw ? ln.indexOf(d->re, d->dcCursor.column(), &match)
+                 : ln.lastIndexOf(d->re, d->dcCursor.column(), &match);
 
-        if (pos > -1) { // we matched a word
+        if (match.hasMatch()) { // we matched a word
             //qCDebug(LOG_KTE)<<"USABLE MATCH";
-            QString m = d->re.cap(1);
+            QString m = match.captured(1);
             if (m != doc->text(*d->liRange) && (d->dcCursor.line() != d->dcRange.start().line() || pos != d->dcRange.start().column())) {
                 // we got good a match! replace text and return.
                 d->isCompleting = true;
diff --git a/src/document/katedocument.cpp b/src/document/katedocument.cpp
--- a/src/document/katedocument.cpp
+++ b/src/document/katedocument.cpp
@@ -84,6 +84,7 @@
 #include <QFileDialog>
 #include <QMimeDatabase>
 #include <QTemporaryFile>
+#include <QRegularExpression>
 
 #include <cmath>
 
@@ -4459,10 +4460,10 @@
 
 void KTextEditor::DocumentPrivate::readVariableLine(QString t, bool onlyViewAndRenderer)
 {
-    static const QRegExp kvLine(QStringLiteral("kate:(.*)"));
-    static const QRegExp kvLineWildcard(QStringLiteral("kate-wildcard\\((.*)\\):(.*)"));
-    static const QRegExp kvLineMime(QStringLiteral("kate-mimetype\\((.*)\\):(.*)"));
-    static const QRegExp kvVar(QStringLiteral("([\\w\\-]+)\\s+([^;]+)"));
+    static const QRegularExpression kvLine(QStringLiteral("kate:(.*)"));
+    static const QRegularExpression kvLineWildcard(QStringLiteral("kate-wildcard\\((.*)\\):(.*)"));
+    static const QRegularExpression kvLineMime(QStringLiteral("kate-mimetype\\((.*)\\):(.*)"));
+    static const QRegularExpression kvVar(QStringLiteral("([\\w\\-]+)\\s+([^;]+)"));
 
     // simple check first, no regex
     // no kate inside, no vars, simple...
@@ -4474,12 +4475,13 @@
     QString s;
 
     // now, try first the normal ones
-    if (kvLine.indexIn(t) > -1) {
-        s = kvLine.cap(1);
+    auto match = kvLine.match(t);
+    if (match.hasMatch()) {
+        s = match.captured(1);
 
         //qCDebug(LOG_KTE) << "normal variable line kate: matched: " << s;
-    } else if (kvLineWildcard.indexIn(t) > -1) { // regex given
-        const QStringList wildcards(kvLineWildcard.cap(1).split(QLatin1Char(';'), QString::SkipEmptyParts));
+    } else if ((match = kvLineWildcard.match(t)).hasMatch()) { // regex given
+        const QStringList wildcards(match.captured(1).split(QLatin1Char(';'), QString::SkipEmptyParts));
         const QString nameOfFile = url().fileName();
 
         bool found = false;
@@ -4494,18 +4496,18 @@
             return;
         }
 
-        s = kvLineWildcard.cap(2);
+        s = match.captured(2);
 
         //qCDebug(LOG_KTE) << "guarded variable line kate-wildcard: matched: " << s;
-    } else if (kvLineMime.indexIn(t) > -1) { // mime-type given
-        const QStringList types(kvLineMime.cap(1).split(QLatin1Char(';'), QString::SkipEmptyParts));
+    } else if ((match = kvLineMime.match(t)).hasMatch()) { // mime-type given
+        const QStringList types(match.captured(1).split(QLatin1Char(';'), QString::SkipEmptyParts));
 
         // no matching type found
         if (!types.contains(mimeType())) {
             return;
         }
 
-        s = kvLineMime.cap(2);
+        s = match.captured(2);
 
         //qCDebug(LOG_KTE) << "guarded variable line kate-mimetype: matched: " << s;
     } else { // nothing found
@@ -4527,13 +4529,13 @@
         << QStringLiteral("font") << QStringLiteral("font-size") << QStringLiteral("scheme");
     int spaceIndent = -1;  // for backward compatibility; see below
     bool replaceTabsSet = false;
-    int p(0);
+    int startPos(0);
 
     QString  var, val;
-    while ((p = kvVar.indexIn(s, p)) > -1) {
-        p += kvVar.matchedLength();
-        var = kvVar.cap(1);
-        val = kvVar.cap(2).trimmed();
+    while ((match = kvVar.match(s, startPos)).hasMatch()) {
+        startPos = match.capturedEnd(0);
+        var = match.captured(1);
+        val = match.captured(2).trimmed();
         bool state; // store booleans here
         int n; // store ints here
 
diff --git a/src/mode/katemodeconfigpage.cpp b/src/mode/katemodeconfigpage.cpp
--- a/src/mode/katemodeconfigpage.cpp
+++ b/src/mode/katemodeconfigpage.cpp
@@ -34,7 +34,7 @@
 #include <KMimeTypeChooser>
 #include "katepartdebug.h"
 
-#include <QRegExp>
+#include <QRegularExpression>
 #include <QCheckBox>
 #include <QComboBox>
 #include <QGroupBox>
@@ -286,7 +286,7 @@
 void ModeConfigPage::showMTDlg()
 {
     QString text = i18n("Select the MimeTypes you want for this file type.\nPlease note that this will automatically edit the associated file extensions as well.");
-    QStringList list = ui->edtMimeTypes->text().split(QRegExp(QLatin1String("\\s*;\\s*")), QString::SkipEmptyParts);
+    QStringList list = ui->edtMimeTypes->text().split(QRegularExpression(QStringLiteral("\\s*;\\s*")), QString::SkipEmptyParts);
     KMimeTypeChooserDialog d(i18n("Select Mime Types"), text, list, QStringLiteral("text"), this);
     if (d.exec() == QDialog::Accepted) {
         // do some checking, warn user if mime types or patterns are removed.
diff --git a/src/mode/katemodemanager.cpp b/src/mode/katemodemanager.cpp
--- a/src/mode/katemodemanager.cpp
+++ b/src/mode/katemodemanager.cpp
@@ -32,7 +32,7 @@
 
 #include <KConfigGroup>
 
-#include <QRegExp>
+#include <QRegularExpression>
 
 #include <QMimeDatabase>
 //END Includes
@@ -164,7 +164,7 @@
         config.writeEntry("Indenter", type->indenter);
 
         QString varLine = type->varLine;
-        if (QRegExp(QLatin1String("kate:(.*)")).indexIn(varLine) < 0) {
+        if (varLine.indexOf(QRegularExpression(QStringLiteral("kate:(.*)"))) < 0) {
             varLine.prepend(QLatin1String("kate: "));
         }
 
diff --git a/src/printing/printpainter.cpp b/src/printing/printpainter.cpp
--- a/src/printing/printpainter.cpp
+++ b/src/printing/printpainter.cpp
@@ -286,7 +286,7 @@
             tags[QStringLiteral("U")].prepend(s);
         }
 
-        QRegExp reTags(QStringLiteral("%([dDfUhuyY])")); // TODO tjeck for "%%<TAG>"
+        QRegularExpression reTags(QStringLiteral("%([dDfUhuyY])")); // TODO tjeck for "%%<TAG>"
 
         if (m_useHeader) {
             pl.headerHeight = QFontMetrics(m_fhFont).height();
@@ -300,13 +300,14 @@
             QMutableStringListIterator it(pl.headerTagList);
             while (it.hasNext()) {
                 QString tag = it.next();
-                int pos = reTags.indexIn(tag);
+                QRegularExpressionMatch match;
+                int pos = tag.indexOf(reTags, 0, &match);
                 QString rep;
                 while (pos > -1) {
-                    rep = tags[reTags.cap(1)];
+                    rep = tags[match.captured(1)];
                     tag.replace((uint)pos, 2, rep);
                     pos += rep.length();
-                    pos = reTags.indexIn(tag, pos);
+                    pos = tag.indexOf(reTags, pos, &match);
                 }
                 it.setValue(tag);
             }
@@ -324,13 +325,14 @@
             QMutableStringListIterator it(pl.footerTagList);
             while (it.hasNext()) {
                 QString tag = it.next();
-                int pos = reTags.indexIn(tag);
+                QRegularExpressionMatch match;
+                int pos = tag.indexOf(reTags, 0, &match);
                 QString rep;
                 while (pos > -1) {
-                    rep = tags[reTags.cap(1)];
+                    rep = tags[match.captured(1)];
                     tag.replace((uint)pos, 2, rep);
                     pos += rep.length();
-                    pos = reTags.indexIn(tag, pos);
+                    pos = tag.indexOf(reTags, pos, &match);
                 }
                 it.setValue(tag);
             }
diff --git a/src/utils/katecmds.cpp b/src/utils/katecmds.cpp
--- a/src/utils/katecmds.cpp
+++ b/src/utils/katecmds.cpp
@@ -33,7 +33,7 @@
 
 #include <KLocalizedString>
 
-#include <QRegExp>
+#include <QRegularExpression>
 
 //BEGIN CoreCommands
 KateCommands::CoreCommands *KateCommands::CoreCommands::m_instance = nullptr;
@@ -204,7 +204,7 @@
     }
 
     //create a list of args
-    QStringList args(_cmd.split(QRegExp(QLatin1String("\\s+")), QString::SkipEmptyParts));
+    QStringList args(_cmd.split(QRegularExpression(QLatin1String("\\s+")), QString::SkipEmptyParts));
     QString cmd(args.takeFirst());
 
     // ALL commands that takes no arguments.
@@ -499,19 +499,20 @@
     QString cmd = _cmd;
 
     // hex, octal, base 9+1
-    QRegExp num(QLatin1String("^char *(0?x[0-9A-Fa-f]{1,4}|0[0-7]{1,6}|[0-9]{1,5})$"));
-    if (num.indexIn(cmd) == -1) {
+    QRegularExpression num(QLatin1String("^char *(0?x[0-9A-Fa-f]{1,4}|0[0-7]{1,6}|[0-9]{1,5})$"));
+    QRegularExpressionMatch match = num.match(cmd);
+    if (!match.hasMatch()) {
         return false;
     }
 
-    cmd = num.cap(1);
+    cmd = match.captured(1);
 
     // identify the base
 
     unsigned short int number = 0;
     int base = 10;
     if (cmd[0] == QLatin1Char('x') || cmd.startsWith(QLatin1String("0x"))) {
-        cmd.remove(QRegExp(QLatin1String("^0?x")));
+        cmd.remove(QRegularExpression(QStringLiteral("^0?x")));
         base = 16;
     } else if (cmd[0] == QLatin1Char('0')) {
         base = 8;