diff --git a/config.inc.php.dist b/config.inc.php.dist
index 9ea52bf..43b43e2 100644
--- a/config.inc.php.dist
+++ b/config.inc.php.dist
@@ -14,6 +14,7 @@
 /*
  * Preconfigured settings for different mail domains.
  * Appropriate set of values is searched by mapping domain of email (from identity) to array key.
+ * Use '*' as a wildcard to match any domain not explicitly listed.
  */
 $config['ident_switch.preconfig'] = [
 
@@ -49,6 +50,13 @@ $config['ident_switch.preconfig'] = [
 		'smtp_host' => 'tls://mail.another.tld:587',
 		'user' => 'mbox',
 	],
+
+	// Wildcard: default settings for any domain not listed above.
+	// '*' => [
+	//	'imap_host' => 'ssl://mail.example.com:993',
+	//	'smtp_host' => 'tls://mail.example.com:587',
+	//	'user' => 'email',
+	// ],
 ];
 
 /*
diff --git a/lib/IdentSwitchPreconfig.php b/lib/IdentSwitchPreconfig.php
index 751c8c1..cf439f9 100644
--- a/lib/IdentSwitchPreconfig.php
+++ b/lib/IdentSwitchPreconfig.php
@@ -38,7 +38,7 @@ class IdentSwitchPreconfig
 		$this->plugin->load_config();
 
 		$cfg = rcmail::get_instance()->config->get('ident_switch.preconfig', []);
-		$cfg = $cfg[$dom] ?? null;
+		$cfg = $cfg[$dom] ?? $cfg['*'] ?? null;
 
 		if ($cfg) {
 			if (empty($cfg['imap_host']) && empty($cfg['host'])) {