diff --git a/common/control.h b/common/control.h
--- a/common/control.h
+++ b/common/control.h
@@ -77,6 +77,11 @@
     void setOutputRetention(const KScreen::OutputPtr &output, OutputRetention value);
     void setOutputRetention(const QString &outputId, const QString &outputName, OutputRetention value);
 
+    qreal getScale(const KScreen::OutputPtr &output) const;
+    qreal getScale(const QString &outputId, const QString &outputName) const;
+    void setScale(const KScreen::OutputPtr &output, qreal value);
+    void setScale(const QString &outputId, const QString &outputName, qreal value);
+
     bool getAutoRotate(const KScreen::OutputPtr &output) const;
     bool getAutoRotate(const QString &outputId, const QString &outputName) const;
     void setAutoRotate(const KScreen::OutputPtr &output, bool value);
@@ -117,6 +122,9 @@
 
     // TODO: scale auto value
 
+    qreal getScale() const;
+    void setScale(qreal value);
+
     bool getAutoRotate() const;
     void setAutoRotate(bool value);
 
diff --git a/common/control.cpp b/common/control.cpp
--- a/common/control.cpp
+++ b/common/control.cpp
@@ -277,6 +277,72 @@
     setOutputs(outputsInfo);
 }
 
+qreal ControlConfig::getScale(const KScreen::OutputPtr &output) const
+{
+    return getScale(output->hashMd5(), output->name());
+}
+
+qreal ControlConfig::getScale(const QString &outputId, const QString &outputName) const
+{
+    const auto retention = getOutputRetention(outputId, outputName);
+    if (retention == OutputRetention::Individual) {
+        const QVariantList outputsInfo = getOutputs();
+        for (const auto variantInfo : outputsInfo) {
+            const QVariantMap info = variantInfo.toMap();
+            if (!infoIsOutput(info, outputId, outputName)) {
+                continue;
+            }
+            const auto val = info[QStringLiteral("scale")];
+            return val.canConvert<qreal>() ? val.toReal() : -1;
+        }
+    }
+    // Retention is global or info for output not in config control file.
+    if (auto *outputControl = getOutputControl(outputId, outputName)) {
+        return outputControl->getScale();
+    }
+
+    // Info for output not found.
+     return -1;
+ }
+
+void ControlConfig::setScale(const KScreen::OutputPtr &output, qreal value)
+{
+    setScale(output->hashMd5(), output->name(), value);
+}
+
+// TODO: combine methods (templated functions)
+void ControlConfig::setScale(const QString &outputId, const QString &outputName, qreal value)
+{
+    QList<QVariant>::iterator it;
+    QVariantList outputsInfo = getOutputs();
+
+    auto setOutputScale = [&outputId, &outputName, value, this]() {
+        if (auto *control = getOutputControl(outputId, outputName)) {
+            control->setScale(value);
+        }
+
+    };
+
+    for (it = outputsInfo.begin(); it != outputsInfo.end(); ++it) {
+        QVariantMap outputInfo = (*it).toMap();
+        if (!infoIsOutput(outputInfo, outputId, outputName)) {
+            continue;
+        }
+        outputInfo[QStringLiteral("scale")] = value;
+        *it = outputInfo;
+        setOutputs(outputsInfo);
+        setOutputScale();
+        return;
+    }
+    // no entry yet, create one
+    auto outputInfo = createOutputInfo(outputId, outputName);
+    outputInfo[QStringLiteral("scale")] = value;
+
+    outputsInfo << outputInfo;
+    setOutputs(outputsInfo);
+    setOutputScale();
+}
+
 bool ControlConfig::getAutoRotate(const KScreen::OutputPtr &output) const
 {
     return getAutoRotate(output->hashMd5(), output->name());
@@ -465,6 +531,21 @@
     return filePathFromHash(m_output->hashMd5());
 }
 
+qreal ControlOutput::getScale() const
+{
+    const auto val = constInfo()[QStringLiteral("scale")];
+    return val.canConvert<qreal>() ? val.toReal() : -1;
+}
+
+void ControlOutput::setScale(qreal value)
+{
+    auto &infoMap = info();
+    if (infoMap.isEmpty()) {
+        infoMap = createOutputInfo(m_output->hashMd5(), m_output->name());
+    }
+    infoMap[QStringLiteral("scale")] = value;
+}
+
 bool ControlOutput::getAutoRotate() const
 {
     const auto val = constInfo()[QStringLiteral("autorotate")];
diff --git a/kcm/config_handler.h b/kcm/config_handler.h
--- a/kcm/config_handler.h
+++ b/kcm/config_handler.h
@@ -47,6 +47,9 @@
     int retention() const;
     void setRetention(int retention);
 
+    qreal scale(const KScreen::OutputPtr &output) const;
+    void setScale(KScreen::OutputPtr &output, qreal scale);
+
     KScreen::OutputPtr replicationSource(const KScreen::OutputPtr &output) const;
     void setReplicationSource(KScreen::OutputPtr &output, const KScreen::OutputPtr &source);
 
@@ -69,6 +72,7 @@
     void primaryOutputSelected(int index);
     void primaryOutputChanged(const KScreen::OutputPtr &output);
     void initOutput(const KScreen::OutputPtr &output);
+    void resetScale(const KScreen::OutputPtr &output);
 
     KScreen::ConfigPtr m_config = nullptr;
     KScreen::ConfigPtr m_initialConfig;
diff --git a/kcm/config_handler.cpp b/kcm/config_handler.cpp
--- a/kcm/config_handler.cpp
+++ b/kcm/config_handler.cpp
@@ -67,9 +67,25 @@
     Q_EMIT outputModelChanged();
 }
 
+void ConfigHandler::resetScale(const KScreen::OutputPtr &output)
+{
+    // Load scale control (either not set, same or windowing system does not transmit scale).
+    const qreal scale = m_control->getScale(output);
+    if (scale > 0) {
+        output->setScale(scale);
+        for (auto initialOutput : m_initialConfig->outputs()) {
+            if (initialOutput->id() == output->id()) {
+                initialOutput->setScale(scale);
+                break;
+            }
+        }
+    }
+}
+
 void ConfigHandler::initOutput(const KScreen::OutputPtr &output)
 {
     if (output->isConnected()) {
+        resetScale(output);
         m_outputs->add(output);
     }
     connect(output.data(), &KScreen::Output::isConnectedChanged,
@@ -87,6 +103,9 @@
             return;
         }
         m_initialConfig = qobject_cast<GetConfigOperation*>(op)->config();
+        for (auto output : m_config->outputs()) {
+            resetScale(output);
+        }
         checkNeedsSave();
     });
 }
@@ -262,6 +281,16 @@
     Q_EMIT changed();
 }
 
+qreal ConfigHandler::scale(const KScreen::OutputPtr &output) const
+{
+    return m_control->getScale(output);
+}
+
+void ConfigHandler::setScale(KScreen::OutputPtr &output, qreal scale)
+{
+    m_control->setScale(output, scale);
+}
+
 KScreen::OutputPtr ConfigHandler::replicationSource(const KScreen::OutputPtr &output) const
 {
     return m_control->getReplicationSource(output);
diff --git a/kcm/output_model.cpp b/kcm/output_model.cpp
--- a/kcm/output_model.cpp
+++ b/kcm/output_model.cpp
@@ -90,7 +90,7 @@
         return false;
     }
 
-    const Output &output = m_outputs[index.row()];
+    Output &output = m_outputs[index.row()];
     switch (role) {
     case PositionRole:
         if (value.canConvert<QPoint>()) {
@@ -149,6 +149,7 @@
         const qreal scale = value.toReal(&ok);
         if (ok && !qFuzzyCompare(output.ptr->scale(), scale)) {
             output.ptr->setScale(scale);
+            m_config->setScale(output.ptr, scale);
             Q_EMIT sizeChanged();
             Q_EMIT dataChanged(index, index, {role, SizeRole});
             return true;