diff --git a/rules-tests/PHPUnit110/Rector/Class_/NamedArgumentForDataProviderRector/Fixture/skip_optional_args.php.inc b/rules-tests/PHPUnit110/Rector/Class_/NamedArgumentForDataProviderRector/Fixture/skip_optional_args.php.inc
new file mode 100644
index 00000000..9191cfc2
--- /dev/null
+++ b/rules-tests/PHPUnit110/Rector/Class_/NamedArgumentForDataProviderRector/Fixture/skip_optional_args.php.inc
@@ -0,0 +1,45 @@
+<?php
+
+namespace Rector\PHPUnit\Tests\PHPUnit110\Rector\MethodCall\NamedArgumentForDataProviderRector\Fixture;
+
+use PHPUnit\Framework\TestCase;
+
+final class TestWithOptionalArguments extends TestCase
+{
+    public static function dataProvider(): Generator
+    {
+        yield [
+            'keyA' => false,
+            'keyC' => true,
+        ];
+    }
+
+    #[\PHPUnit\Framework\Attributes\DataProvider('dataProvider')]
+    public function testFilter(bool $keyA, bool $keyB = false, bool $keyC = false): void
+    {
+    }
+}
+?>
+-----
+<?php
+
+namespace Rector\PHPUnit\Tests\PHPUnit110\Rector\MethodCall\NamedArgumentForDataProviderRector\Fixture;
+
+use PHPUnit\Framework\TestCase;
+
+final class TestWithOptionalArguments extends TestCase
+{
+    public static function dataProvider(): Generator
+    {
+        yield [
+            'keyA' => false,
+            'keyC' => true,
+        ];
+    }
+
+    #[\PHPUnit\Framework\Attributes\DataProvider('dataProvider')]
+    public function testFilter(bool $keyA, bool $keyB = false, bool $keyC = false): void
+    {
+    }
+}
+?>
diff --git a/rules/PHPUnit110/Rector/Class_/NamedArgumentForDataProviderRector.php b/rules/PHPUnit110/Rector/Class_/NamedArgumentForDataProviderRector.php
index 47d13c12..d8cff038 100644
--- a/rules/PHPUnit110/Rector/Class_/NamedArgumentForDataProviderRector.php
+++ b/rules/PHPUnit110/Rector/Class_/NamedArgumentForDataProviderRector.php
@@ -239,6 +239,11 @@ private function refactorArrayKey(Array_ $array, array $dataProviderNameMapping)
             return false;
         }
 
+        // Skip already named arguments - optional parameters can be left out
+        if ($allArrayKeyNames !== [] && array_diff($allArrayKeyNames, $dataProviderNameMapping) === []) {
+            return false;
+        }
+
         foreach ($array->items as $arrayIndex => $arrayItem) {
             if (! isset($dataProviderNameMapping[$arrayIndex])) {
                 continue;