diff --git a/doc/release-notes.md b/doc/release-notes.md
--- a/doc/release-notes.md
+++ b/doc/release-notes.md
@@ -5,9 +5,20 @@
   <https://download.bitcoinabc.org/0.26.3/>
 
 This release includes the following features and fixes:
+
+RPC changes
+-----------
+
  - A new `total_fee` field showing the total fees for all transactions in the
    mempool has been added to the `getmempoolinfo` RPC.
  - Added a new `getavalancheproofs` RPC to retrieve all avalanche proof IDs
    tracked by the node.
  - Added a new field `immature_stake_amount` to `getavalancheinfo` to report
    the total amount of stake that will mature within the next 2016 blocks.
+
+P2P and network changes
+-----------------------
+
+ - Added NAT-PMP port mapping support via [`libnatpmp`](https://miniupnp.tuxfamily.org/libnatpmp.html).
+   Use the `-natpmp` command line option to use NAT-PMP to map the listening port. If both UPnP
+   and NAT-PMP are enabled, a successful allocation from UPnP prevails over one from NAT-PMP.
diff --git a/doc/tor.md b/doc/tor.md
--- a/doc/tor.md
+++ b/doc/tor.md
@@ -197,7 +197,7 @@
 
 	./bitcoind ... -discover
 
-and open port 8333 on your firewall (or use `-upnp`).
+and open port 8333 on your firewall (or use port mapping, i.e., `-upnp` or `-natpmp`).
 
 If you only want to use Tor to reach .onion addresses, but not use it as a proxy
 for normal IPv4/IPv6 communication, use:
diff --git a/src/qt/forms/optionsdialog.ui b/src/qt/forms/optionsdialog.ui
--- a/src/qt/forms/optionsdialog.ui
+++ b/src/qt/forms/optionsdialog.ui
@@ -259,6 +259,16 @@
          </property>
         </widget>
        </item>
+       <item>
+        <widget class="QCheckBox" name="mapPortNatpmp">
+         <property name="toolTip">
+          <string>Automatically open the Bitcoin ABC client port on the router. This only works when your router supports NAT-PMP and it is enabled. The external port could be random.</string>
+         </property>
+         <property name="text">
+          <string>Map port using NA&amp;T-PMP</string>
+         </property>
+        </widget>
+       </item>
        <item>
         <widget class="QCheckBox" name="allowIncoming">
          <property name="toolTip">
diff --git a/src/qt/optionsdialog.cpp b/src/qt/optionsdialog.cpp
--- a/src/qt/optionsdialog.cpp
+++ b/src/qt/optionsdialog.cpp
@@ -47,6 +47,9 @@
 /* Network elements init */
 #ifndef USE_UPNP
     ui->mapPortUpnp->setEnabled(false);
+#endif
+#ifndef USE_NATPMP
+    ui->mapPortNatpmp->setEnabled(false);
 #endif
     connect(this, &QDialog::accepted, [this]() {
         QSettings settings;
@@ -266,6 +269,7 @@
 
     /* Network */
     mapper->addMapping(ui->mapPortUpnp, OptionsModel::MapPortUPnP);
+    mapper->addMapping(ui->mapPortNatpmp, OptionsModel::MapPortNatpmp);
     mapper->addMapping(ui->allowIncoming, OptionsModel::Listen);
 
     mapper->addMapping(ui->connectSocks, OptionsModel::ProxyUse);