diff --git a/.github/workflows/code_analysis.yaml b/.github/workflows/code_analysis.yaml
index d4869162c92..33831a4260f 100644
--- a/.github/workflows/code_analysis.yaml
+++ b/.github/workflows/code_analysis.yaml
@@ -53,7 +53,7 @@ jobs:
                     -
                         name: 'Active Classes'
                         run: |
-                            vendor/bin/class-leak check bin config src rules utils --skip-suffix "Rector" --skip-type="Rector\\Utils\\Compiler\\Unprefixer" --skip-type="Rector\\NodeCollector\\BinaryOpConditionsCollector" --skip-type="Rector\\Set\\Contract\\SetListInterface" --skip-type="Rector\\DependencyInjection\\PHPStan\\RichParserFactory" --skip-type="Rector\\Utils\\PHPStan\\Tests\\Rule\\SingleServiceRegistrationRule\\Source\\DuplicateRegistrationFactory" --skip-type="Rector\\Utils\\PHPStan\\Tests\\Rule\\SingleServiceRegistrationRule\\Source\\SingleRegistrationFactory" --skip-type="Rector\\ChangesReporting\\Contract\\Output\\OutputFormatterInterface" --skip-type="Rector\\NodeTypeResolver\\Contract\\NodeTypeResolverInterface" --skip-type="Rector\\CodingStyle\\Contract\\ClassNameImport\\ClassNameImportSkipVoterInterface" --skip-type="Rector\\Php80\\Contract\\ConverterAttributeDecoratorInterface" --skip-type="Rector\\NodeNameResolver\\Contract\\NodeNameResolverInterface" --skip-type="Rector\\StaticTypeMapper\\Contract\\PhpDocParser\\PhpDocTypeMapperInterface" --skip-type="Rector\\PhpAttribute\\Contract\\AnnotationToAttributeMapperInterface" --skip-type="Rector\\PHPStanStaticTypeMapper\\Contract\\TypeMapperInterface" --skip-type="Rector\\StaticTypeMapper\\Contract\\PhpParser\\PhpParserNodeMapperInterface"
+                            vendor/bin/class-leak check bin config src rules utils --skip-suffix "Rector" --skip-type="Rector\\Utils\\Compiler\\Unprefixer" --skip-type="Rector\\NodeCollector\\BinaryOpConditionsCollector" --skip-type="Rector\\Set\\Contract\\SetListInterface" --skip-type="Rector\\DependencyInjection\\PHPStan\\RichParserFactory" --skip-type="Rector\\Utils\\PHPStan\\Tests\\Rule\\SingleServiceRegistrationRule\\Source\\DuplicateRegistrationFactory" --skip-type="Rector\\Utils\\PHPStan\\Tests\\Rule\\SingleServiceRegistrationRule\\Source\\SingleRegistrationFactory" --skip-type="Rector\\ChangesReporting\\Contract\\Output\\OutputFormatterInterface" --skip-type="Rector\\NodeTypeResolver\\Contract\\NodeTypeResolverInterface" --skip-type="Rector\\CodingStyle\\Contract\\ClassNameImport\\ClassNameImportSkipVoterInterface" --skip-type="Rector\\Php80\\Contract\\ConverterAttributeDecoratorInterface" --skip-type="Rector\\NodeNameResolver\\Contract\\NodeNameResolverInterface" --skip-type="Rector\\StaticTypeMapper\\Contract\\PhpDocParser\\PhpDocTypeMapperInterface" --skip-type="Rector\\PhpAttribute\\Contract\\AnnotationToAttributeMapperInterface" --skip-type="Rector\\PHPStanStaticTypeMapper\\Contract\\TypeMapperInterface" --skip-type="Rector\\StaticTypeMapper\\Contract\\PhpParser\\PhpParserNodeMapperInterface" --skip-type="Rector\\Utils\\PHPUnit\\SlowestTests\\SlowTestExtension"
 
                     -
                         name: 'Compatible PHPStan versions'
diff --git a/phpunit.xml b/phpunit.xml
index 37c4eb12d7f..c134897098b 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -21,4 +21,8 @@
     <php>
         <ini name="memory_limit" value="-1"/>
     </php>
+
+    <extensions>
+        <bootstrap class="Rector\Utils\PHPUnit\SlowestTests\SlowTestExtension"/>
+    </extensions>
 </phpunit>
diff --git a/utils/PHPUnit/SlowestTests/RunnerFinishedSubscriber.php b/utils/PHPUnit/SlowestTests/RunnerFinishedSubscriber.php
new file mode 100644
index 00000000000..42452ea0809
--- /dev/null
+++ b/utils/PHPUnit/SlowestTests/RunnerFinishedSubscriber.php
@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\Utils\PHPUnit\SlowestTests;
+
+use PHPUnit\Event\TestRunner\ExecutionFinished;
+use PHPUnit\Event\TestRunner\ExecutionFinishedSubscriber;
+
+final readonly class RunnerFinishedSubscriber implements ExecutionFinishedSubscriber
+{
+    public function __construct(
+        private SlowTestReporter $slowTestReporter
+    ) {
+    }
+
+    public function notify(ExecutionFinished $event): void
+    {
+        $this->slowTestReporter->printSlowest();
+    }
+}
diff --git a/utils/PHPUnit/SlowestTests/SlowTestExtension.php b/utils/PHPUnit/SlowestTests/SlowTestExtension.php
new file mode 100644
index 00000000000..fde3cf46b27
--- /dev/null
+++ b/utils/PHPUnit/SlowestTests/SlowTestExtension.php
@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\Utils\PHPUnit\SlowestTests;
+
+use PHPUnit\Runner\Extension\Extension;
+use PHPUnit\Runner\Extension\Facade;
+use PHPUnit\Runner\Extension\ParameterCollection;
+use PHPUnit\TextUI\Configuration\Configuration;
+
+final class SlowTestExtension implements Extension
+{
+    public function bootstrap(Configuration $configuration, Facade $facade, ParameterCollection $parameters): void
+    {
+        $slowTestReporter = new SlowTestReporter();
+
+        $facade->registerSubscribers(
+            new TestPreparedSubscriber($slowTestReporter),
+            new TestFinishedSubscriber($slowTestReporter),
+            new RunnerFinishedSubscriber($slowTestReporter),
+        );
+    }
+}
diff --git a/utils/PHPUnit/SlowestTests/SlowTestReporter.php b/utils/PHPUnit/SlowestTests/SlowTestReporter.php
new file mode 100644
index 00000000000..8e7e0cb8c7a
--- /dev/null
+++ b/utils/PHPUnit/SlowestTests/SlowTestReporter.php
@@ -0,0 +1,67 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\Utils\PHPUnit\SlowestTests;
+
+final class SlowTestReporter
+{
+    private const int LIMIT = 25;
+
+    /**
+     * Only report tests slower than this, to keep the list signal-heavy.
+     */
+    private const float THRESHOLD_SECONDS = 0.5;
+
+    /**
+     * Seconds since run start, captured when a test is prepared, keyed by test id.
+     * @var array<string, float>
+     */
+    private array $startedAt = [];
+
+    /**
+     * Test name => accumulated duration in seconds (summed across data-provider fixtures).
+     * @var array<string, float>
+     */
+    private array $durations = [];
+
+    public function testPrepared(string $testId, float $secondsSinceStart): void
+    {
+        $this->startedAt[$testId] = $secondsSinceStart;
+    }
+
+    public function testFinished(string $testId, string $testName, float $secondsSinceStart): void
+    {
+        if (! isset($this->startedAt[$testId])) {
+            return;
+        }
+
+        $this->durations[$testName] = ($this->durations[$testName] ?? 0.0) + ($secondsSinceStart - $this->startedAt[$testId]);
+        unset($this->startedAt[$testId]);
+    }
+
+    public function printSlowest(): void
+    {
+        $slowDurations = array_filter(
+            $this->durations,
+            static fn (float $seconds): bool => $seconds >= self::THRESHOLD_SECONDS
+        );
+
+        if ($slowDurations === []) {
+            return;
+        }
+
+        arsort($slowDurations);
+        $slowDurations = array_slice($slowDurations, 0, self::LIMIT, true);
+
+        echo PHP_EOL . sprintf('%d slowest tests (>= %.1fs):', count($slowDurations), self::THRESHOLD_SECONDS) . PHP_EOL;
+
+        $position = 1;
+        foreach ($slowDurations as $testName => $seconds) {
+            echo sprintf('%3d. %6.2fs  %s', $position, $seconds, $testName) . PHP_EOL;
+            ++$position;
+        }
+
+        echo PHP_EOL;
+    }
+}
diff --git a/utils/PHPUnit/SlowestTests/TestFinishedSubscriber.php b/utils/PHPUnit/SlowestTests/TestFinishedSubscriber.php
new file mode 100644
index 00000000000..79dc10d26d1
--- /dev/null
+++ b/utils/PHPUnit/SlowestTests/TestFinishedSubscriber.php
@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\Utils\PHPUnit\SlowestTests;
+
+use PHPUnit\Event\Code\TestMethod;
+use PHPUnit\Event\Test\Finished;
+use PHPUnit\Event\Test\FinishedSubscriber;
+
+final readonly class TestFinishedSubscriber implements FinishedSubscriber
+{
+    public function __construct(
+        private SlowTestReporter $slowTestReporter
+    ) {
+    }
+
+    public function notify(Finished $event): void
+    {
+        $test = $event->test();
+
+        // group all data-provider fixtures under one test method, so a slow rule shows as a single entry
+        $reportName = $test instanceof TestMethod ? $test->className() . '::' . $test->methodName() : $test->name();
+
+        $this->slowTestReporter->testFinished(
+            $test->id(),
+            $reportName,
+            $event->telemetryInfo()->durationSinceStart()->asFloat()
+        );
+    }
+}
diff --git a/utils/PHPUnit/SlowestTests/TestPreparedSubscriber.php b/utils/PHPUnit/SlowestTests/TestPreparedSubscriber.php
new file mode 100644
index 00000000000..49426b9de78
--- /dev/null
+++ b/utils/PHPUnit/SlowestTests/TestPreparedSubscriber.php
@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\Utils\PHPUnit\SlowestTests;
+
+use PHPUnit\Event\Test\Prepared;
+use PHPUnit\Event\Test\PreparedSubscriber;
+
+final readonly class TestPreparedSubscriber implements PreparedSubscriber
+{
+    public function __construct(
+        private SlowTestReporter $slowTestReporter
+    ) {
+    }
+
+    public function notify(Prepared $event): void
+    {
+        $this->slowTestReporter->testPrepared(
+            $event->test()->id(),
+            $event->telemetryInfo()->durationSinceStart()->asFloat()
+        );
+    }
+}