diff --git a/launcher/InstanceList.cpp b/launcher/InstanceList.cpp
index 1339499c7..e366b1cf4 100644
--- a/launcher/InstanceList.cpp
+++ b/launcher/InstanceList.cpp
@@ -145,6 +145,30 @@ QStringList InstanceList::getLinkedInstancesById(const QString& id) const
     return linkedInstances;
 }
 
+QStringList InstanceList::groupOrder() const
+{
+    return m_groupOrder;
+}
+
+void InstanceList::moveGroup(const QString& group, int toIndex)
+{
+    int fromIndex = m_groupOrder.indexOf(group);
+    if (fromIndex < 0)
+        return;
+
+    int size = m_groupOrder.size();
+    toIndex = qBound(0, toIndex, size);
+    if (fromIndex == toIndex)
+        return;
+
+    QString name = m_groupOrder.takeAt(fromIndex);
+    // After takeAt, insert position shifts if target was after the removed position
+    int insertAt = (fromIndex < toIndex) ? (toIndex - 1) : toIndex;
+    m_groupOrder.insert(insertAt, name);
+    emit groupOrderChanged();
+    saveGroupList();
+}
+
 int InstanceList::rowCount(const QModelIndex& parent) const
 {
     Q_UNUSED(parent);
@@ -293,6 +317,8 @@ void InstanceList::deleteGroup(const GroupId& name)
     }
     if (removed)
         saveGroupList();
+    m_groupOrder.removeAll(name);
+    emit groupOrderChanged();
 }
 
 void InstanceList::renameGroup(const QString& src, const QString& dst)
@@ -318,6 +344,10 @@ void InstanceList::renameGroup(const QString& src, const QString& dst)
     }
     if (modified)
         saveGroupList();
+    int idx = m_groupOrder.indexOf(src);
+    if (idx >= 0)
+        m_groupOrder[idx] = dst;
+    emit groupOrderChanged();
 }
 
 bool InstanceList::isGroupCollapsed(const QString& group)
@@ -692,7 +722,11 @@ void InstanceList::increaseGroupCount(const QString& group)
     if (group.isEmpty())
         return;
 
+    bool wasNew = !m_groupNameCache.contains(group);
     ++m_groupNameCache[group];
+    if (wasNew && !m_groupOrder.contains(group)) {
+        m_groupOrder.append(group);
+    }
 }
 
 void InstanceList::decreaseGroupCount(const QString& group)
@@ -703,6 +737,7 @@ void InstanceList::decreaseGroupCount(const QString& group)
     if (--m_groupNameCache[group] < 1) {
         m_groupNameCache.remove(group);
         m_collapsedGroups.remove(group);
+        m_groupOrder.removeAll(group);
     }
 }
 
@@ -757,6 +792,16 @@ void InstanceList::saveGroupList()
         ungrouped.insert("hidden", QJsonValue(true));
         toplevel.insert("ungrouped", ungrouped);
     }
+    // Save group order (deduplicate to prevent silent corruption)
+    QJsonArray orderArr;
+    QStringList savedOrder;
+    for (const auto& name : m_groupOrder) {
+        if (!savedOrder.contains(name) && (name.isEmpty() || m_groupNameCache.contains(name))) {
+            savedOrder.append(name);
+            orderArr.append(name);
+        }
+    }
+    toplevel.insert("groupOrder", orderArr);
     QJsonDocument doc(toplevel);
     try {
         FS::write(groupFileName, doc.toJson());
@@ -772,9 +817,13 @@ void InstanceList::loadGroupList()
 
     QString groupFileName = m_instDir + "/instgroups.json";
 
-    // if there's no group file, fail
-    if (!QFileInfo(groupFileName).exists())
+    // if there's no group file, set up default state
+    if (!QFileInfo(groupFileName).exists()) {
+        m_groupOrder.clear();
+        m_groupOrder.append("");
+        m_groupsLoaded = true;
         return;
+    }
 
     QByteArray jsonData;
     try {
@@ -815,6 +864,16 @@ void InstanceList::loadGroupList()
 
     m_instanceGroupIndex.clear();
     m_groupNameCache.clear();
+    m_groupOrder.clear();
+
+    // Load saved group order FIRST, so increaseGroupCount won't re-add groups out of order
+    if (rootObj.value("groupOrder").isArray()) {
+        QJsonArray orderArr = rootObj.value("groupOrder").toArray();
+        for (const auto& val : orderArr) {
+            QString name = val.toString();
+            m_groupOrder.append(name);
+        }
+    }
 
     // Iterate through all the groups.
     QJsonObject groupMapping = rootObj.value("groups").toObject();
@@ -862,6 +921,23 @@ void InstanceList::loadGroupList()
         // empty string represents ungrouped "group"
         m_collapsedGroups.insert("");
     }
+
+    // Deduplicate group order (defense against previously-corrupted data)
+    QStringList uniqueOrder;
+    for (const auto& name : m_groupOrder) {
+        if (!uniqueOrder.contains(name))
+            uniqueOrder.append(name);
+    }
+    m_groupOrder = uniqueOrder;
+
+    // Treat ungrouped group (empty string) as a regular group for ordering
+    if (m_groupOrder.isEmpty()) {
+        m_groupOrder = m_groupNameCache.keys();
+        m_groupOrder.sort();
+    }
+    if (!m_groupOrder.contains(""))
+        m_groupOrder.append("");
+
     m_groupsLoaded = true;
     qDebug() << "Group list loaded.";
 }
diff --git a/launcher/InstanceList.h b/launcher/InstanceList.h
index f0a92d273..8f3bdc06b 100644
--- a/launcher/InstanceList.h
+++ b/launcher/InstanceList.h
@@ -158,8 +158,11 @@ class InstanceList : public QAbstractListModel {
     QMimeData* mimeData(const QModelIndexList& indexes) const override;
 
     QStringList getLinkedInstancesById(const QString& id) const;
+    QStringList groupOrder() const;
+    void moveGroup(const QString& group, int toIndex);
 
    signals:
+    void groupOrderChanged();
     void dataIsInvalid();
     void instancesChanged();
     void instanceSelectRequest(QString instanceId);
@@ -195,6 +198,7 @@ class InstanceList : public QAbstractListModel {
     std::vector<std::unique_ptr<BaseInstance>> m_instances;
     // id -> refs
     QMap<QString, int> m_groupNameCache;
+    QStringList m_groupOrder;
 
     SettingsObject* m_globalSettings;
     QString m_instDir;
diff --git a/launcher/ui/instanceview/InstanceView.cpp b/launcher/ui/instanceview/InstanceView.cpp
index 9a24b7990..d1bc15e7f 100644
--- a/launcher/ui/instanceview/InstanceView.cpp
+++ b/launcher/ui/instanceview/InstanceView.cpp
@@ -38,6 +38,7 @@
 #include <QAccessible>
 #include <QApplication>
 #include <QCache>
+
 #include <QDrag>
 #include <QFont>
 #include <QListView>
@@ -46,6 +47,7 @@
 #include <QPainter>
 #include <QPersistentModelIndex>
 #include <QScrollBar>
+#include <QSet>
 #include <QtMath>
 
 #include "VisualGroup.h"
@@ -202,7 +204,23 @@ void InstanceView::updateGeometries()
     }
 
     qDeleteAll(m_groups);
-    m_groups = cats.values();
+    m_groups.clear();
+
+    // Build ordered group list from custom group order
+    auto instanceList = APPLICATION->instances();
+    auto groupOrder = instanceList->groupOrder();
+    QSet<QString> placed;
+    for (const auto& groupName : groupOrder) {
+        if (cats.contains(groupName)) {
+            m_groups.append(cats.take(groupName));
+            placed.insert(groupName);
+        }
+    }
+    // Append remaining groups (not in order) alphabetically
+    auto remaining = cats.values();
+    std::sort(remaining.begin(), remaining.end(), [](VisualGroup* a, VisualGroup* b) { return a->text.localeAwareCompare(b->text) < 0; });
+    m_groups.append(remaining);
+
     updateScrollbar();
     viewport()->update();
 }
@@ -283,12 +301,20 @@ void InstanceView::mousePressEvent(QMouseEvent* event)
     m_pressedIndex = index;
     m_pressedAlreadySelected = selectionModel()->isSelected(m_pressedIndex);
     m_pressedPosition = geometryPos;
+    m_draggingGroup = false;
+    m_draggedGroupName.clear();
+    m_groupDragTargetIndex = -1;
 
     if (event->button() == Qt::LeftButton) {
         VisualGroup::HitResults hitResult;
         m_pressedCategory = categoryAt(geometryPos, hitResult);
-        if (m_pressedCategory && hitResult & VisualGroup::CheckboxHit) {
-            setState(m_pressedCategory->collapsed ? ExpandingState : CollapsingState);
+        if (m_pressedCategory && hitResult & VisualGroup::HeaderHit) {
+            // Always allow drag from header, collapse also possible on click
+            m_draggingGroup = true;
+            m_draggedGroupName = m_pressedCategory->text;
+            if (hitResult & VisualGroup::CheckboxHit) {
+                setState(m_pressedCategory->collapsed ? ExpandingState : CollapsingState);
+            }
             event->accept();
             return;
         }
@@ -325,6 +351,39 @@ void InstanceView::mouseMoveEvent(QMouseEvent* event)
     QPoint visualPos = event->pos();
     QPoint geometryPos = event->pos() + offset();
 
+    if (m_draggingGroup) {
+        topLeft = m_pressedPosition - offset();
+        qreal dist = (topLeft - event->pos()).manhattanLength();
+        qreal threshold = QApplication::startDragDistance();
+        if (dist > threshold) {
+            // Drag preview: compute visual target index and show indicator
+            setState(NoState);
+            QPoint cursorPos = geometryPos;
+            m_groupDragTargetIndex = -1;
+            for (int i = 0; i < m_groups.size(); i++) {
+                if (m_groups[i]->text == m_draggedGroupName)
+                    continue;
+                int gTop = m_groups[i]->verticalPosition();
+                int gBot = gTop + m_groups[i]->totalHeight();
+                int hMid = gTop + VisualGroup::headerHeight() / 2;
+                if (cursorPos.y() < hMid) {
+                    m_groupDragTargetIndex = i;
+                    break;
+                } else if (cursorPos.y() < gBot) {
+                    m_groupDragTargetIndex = i + 1;
+                    break;
+                }
+            }
+            if (m_groupDragTargetIndex < 0)
+                m_groupDragTargetIndex = m_groups.size();
+            if (m_groupDragTargetIndex > m_groups.size())
+                m_groupDragTargetIndex = m_groups.size();
+            viewport()->update();
+            return;
+        }
+        return;
+    }
+
     if (state() == ExpandingState || state() == CollapsingState) {
         return;
     }
@@ -368,6 +427,35 @@ void InstanceView::mouseReleaseEvent(QMouseEvent* event)
 {
     executeDelayedItemsLayout();
 
+    // Commit group drag reorder on release
+    if (m_draggingGroup && m_groupDragTargetIndex >= 0) {
+        auto groupOrder = APPLICATION->instances()->groupOrder();
+        int currentOrderIdx = groupOrder.indexOf(m_draggedGroupName);
+        if (currentOrderIdx >= 0) {
+            // Convert visual target index to groupOrder index
+            int orderTarget = 0;
+            for (int i = 0; i < m_groupDragTargetIndex && i < m_groups.size(); i++) {
+                if (m_groups[i]->text == m_draggedGroupName)
+                    continue;
+                int orderPos = groupOrder.indexOf(m_groups[i]->text);
+                if (orderPos >= 0 && orderPos >= orderTarget)
+                    orderTarget = orderPos + 1;
+            }
+            // Clamp to valid range
+            if (orderTarget > groupOrder.size())
+                orderTarget = groupOrder.size();
+            if (orderTarget != currentOrderIdx) {
+                APPLICATION->instances()->moveGroup(m_draggedGroupName, orderTarget);
+                updateGeometries();
+            }
+        }
+        viewport()->update();
+    }
+
+    m_draggingGroup = false;
+    m_draggedGroupName.clear();
+    m_groupDragTargetIndex = -1;
+
     QPoint visualPos = event->pos();
     QPoint geometryPos = event->pos() + offset();
     QPersistentModelIndex index = indexAt(visualPos);
@@ -524,6 +612,21 @@ void InstanceView::paintEvent([[maybe_unused]] QPaintEvent* event)
         option.rect = backup;
     }
 
+    // Draw group drag drop indicator
+    if (m_groupDragTargetIndex >= 0) {
+        int indicatorY = 0;
+        if (m_groupDragTargetIndex < m_groups.size()) {
+            indicatorY = m_groups[m_groupDragTargetIndex]->verticalPosition() - verticalOffset();
+        } else if (!m_groups.isEmpty()) {
+            auto* last = m_groups.last();
+            indicatorY = last->verticalPosition() + last->totalHeight() - verticalOffset();
+        }
+        painter.save();
+        painter.setPen(QPen(Qt::white, 1));
+        painter.drawLine(m_leftMargin, indicatorY, wpWidth - m_rightMargin, indicatorY);
+        painter.restore();
+    }
+
     for (int i = 0; i < model()->rowCount(); ++i) {
         const QModelIndex index = model()->index(i, 0);
         if (isIndexHidden(index)) {
diff --git a/launcher/ui/instanceview/InstanceView.h b/launcher/ui/instanceview/InstanceView.h
index 5d9dbf729..b47b6c1fe 100644
--- a/launcher/ui/instanceview/InstanceView.h
+++ b/launcher/ui/instanceview/InstanceView.h
@@ -139,6 +139,11 @@ class InstanceView : public QAbstractItemView {
     QItemSelectionModel::SelectionFlag m_ctrlDragSelectionFlag;
     QPoint m_lastDragPosition;
 
+    // group drag-reorder state
+    bool m_draggingGroup = false;
+    QString m_draggedGroupName;
+    int m_groupDragTargetIndex = -1;
+
     VisualGroup* category(const QModelIndex& index) const;
     VisualGroup* category(const QString& cat) const;
     VisualGroup* categoryAt(const QPoint& pos, VisualGroup::HitResults& result) const;