diff --git a/src/qt/bitcoin.h b/src/qt/bitcoin.h
--- a/src/qt/bitcoin.h
+++ b/src/qt/bitcoin.h
@@ -71,6 +71,8 @@
     void parameterSetup();
     /// Create options model
     void createOptionsModel(bool resetSettings);
+    /// Update prune value
+    void SetPrune(bool prune, bool force = false);
     /// Create main window
     void createWindow(const Config *, const NetworkStyle *networkStyle);
     /// Create splash screen
diff --git a/src/qt/bitcoin.cpp b/src/qt/bitcoin.cpp
--- a/src/qt/bitcoin.cpp
+++ b/src/qt/bitcoin.cpp
@@ -301,6 +301,10 @@
     m_node.initParameterInteraction();
 }
 
+void BitcoinApplication::SetPrune(bool prune, bool force) {
+    optionsModel->SetPrune(prune, force);
+}
+
 void BitcoinApplication::requestInitialize(
     Config &config, RPCServer &rpcServer,
     HTTPRPCRequestProcessor &httpRPCRequestProcessor) {
diff --git a/src/qt/optionsmodel.h b/src/qt/optionsmodel.h
--- a/src/qt/optionsmodel.h
+++ b/src/qt/optionsmodel.h
@@ -82,6 +82,9 @@
         return strOverriddenByCommandLine;
     }
 
+    /* Explicit setters */
+    void SetPrune(bool prune, bool force = false);
+
     /* Restart flag helper */
     void setRestartRequired(bool fRequired);
     bool isRestartRequired() const;
diff --git a/src/qt/optionsmodel.cpp b/src/qt/optionsmodel.cpp
--- a/src/qt/optionsmodel.cpp
+++ b/src/qt/optionsmodel.cpp
@@ -104,14 +104,7 @@
     if (!settings.contains("nPruneSize")) {
         settings.setValue("nPruneSize", 2);
     }
-    // Convert prune size from GB to MiB:
-    const uint64_t nPruneSizeMiB =
-        (settings.value("nPruneSize").toInt() * GB_BYTES) >> 20;
-    if (!m_node.softSetArg("-prune", settings.value("bPrune").toBool()
-                                         ? std::to_string(nPruneSizeMiB)
-                                         : "0")) {
-        addOverriddenOption("-prune");
-    }
+    SetPrune(settings.value("bPrune").toBool());
 
     if (!settings.contains("nDatabaseCache")) {
         settings.setValue("nDatabaseCache", (qint64)nDefaultDbCache);
@@ -290,6 +283,22 @@
         .arg(DEFAULT_GUI_PROXY_PORT);
 }
 
+void OptionsModel::SetPrune(bool prune, bool force) {
+    QSettings settings;
+    settings.setValue("bPrune", prune);
+    // Convert prune size from GB to MiB:
+    const uint64_t nPruneSizeMiB =
+        (settings.value("nPruneSize").toInt() * GB_BYTES) >> 20;
+    std::string prune_val = prune ? std::to_string(nPruneSizeMiB) : "0";
+    if (force) {
+        m_node.forceSetArg("-prune", prune_val);
+        return;
+    }
+    if (!m_node.softSetArg("-prune", prune_val)) {
+        addOverriddenOption("-prune");
+    }
+}
+
 // read QSettings values and return them
 QVariant OptionsModel::data(const QModelIndex &index, int role) const {
     if (role == Qt::EditRole) {