diff --git a/src/globals/ext-tests/iconv.php b/src/globals/ext-tests/iconv.php
new file mode 100644
index 00000000..6bf32839
--- /dev/null
+++ b/src/globals/ext-tests/iconv.php
@@ -0,0 +1,6 @@
+<?php
+
+declare(strict_types=1);
+
+assert(function_exists('iconv'));
+assert(iconv('UTF-8', 'CP437', 'foo') === 'foo');
diff --git a/src/globals/test-extensions.php b/src/globals/test-extensions.php
index 6b2fea44..d0f018bb 100644
--- a/src/globals/test-extensions.php
+++ b/src/globals/test-extensions.php
@@ -20,7 +20,7 @@ $upx = true;
 // If you want to test your added extensions and libs, add below (comma separated, example `bcmath,openssl`).
 $extensions = match (PHP_OS_FAMILY) {
     'Linux', 'Darwin' => 'iconv',
-    'Windows' => 'amqp,apcu',
+    'Windows' => 'amqp,apcu,iconv',
 };
 
 // If you want to test lib-suggests feature with extension, add them below (comma separated, example `libwebp,libavif`).