diff --git a/changelog/_unreleased/2024-04-15-add-language-to-send-mail-event.md b/changelog/_unreleased/2024-04-15-add-language-to-send-mail-event.md
index d461591ed12..ac8dda40283 100644
--- a/changelog/_unreleased/2024-04-15-add-language-to-send-mail-event.md
+++ b/changelog/_unreleased/2024-04-15-add-language-to-send-mail-event.md
@@ -5,9 +5,6 @@ author: Jasper Peeters
 author_email: jasper.peeters@meteor.be
 author_github: JasperP98
 ---
-
 # Core
-
-* Add `LanguageAware` and a `LanguageStorer` class to allow a specific language for flow events
-
-* Add language id property to databag for mail events
+* Added `LanguageAware` and a `LanguageStorer` class to allow a specific language for flow events
+* Added language id property to databag for mail events
diff --git a/tests/unit/Core/Content/Flow/Dispatching/Action/SendMailActionTest.php b/tests/unit/Core/Content/Flow/Dispatching/Action/SendMailActionTest.php
index df47ae72eb9..84431197f34 100644
--- a/tests/unit/Core/Content/Flow/Dispatching/Action/SendMailActionTest.php
+++ b/tests/unit/Core/Content/Flow/Dispatching/Action/SendMailActionTest.php
@@ -25,6 +25,7 @@
 use Shopware\Core\Framework\DataAbstractionLayer\EntityRepository;
 use Shopware\Core\Framework\DataAbstractionLayer\Search\EntitySearchResult;
 use Shopware\Core\Framework\Event\EventData\MailRecipientStruct;
+use Shopware\Core\Framework\Event\LanguageAware;
 use Shopware\Core\Framework\Event\MailAware;
 use Shopware\Core\Framework\Event\OrderAware;
 use Shopware\Core\Framework\Log\Package;
@@ -265,6 +266,7 @@ public function testActionExecuted(?string $replyTo, array $exptectedReplyTo = [
                 'subject' => null,
                 'mediaIds' => [],
                 'senderName' => null,
+                'languageId' => null,
                 'attachmentsConfig' => new MailAttachmentsConfig(
                     Context::createDefaultContext(),
                     $this->mailTemplate,
@@ -423,6 +425,7 @@ public function testActionExecutedWithRecipientFromStoreData(): void
             'recipient' => ['type' => 'customer'],
             'documentTypeIds' => null,
         ]);
+        $languageId = Uuid::randomHex();
 
         $expected = [
             'data' => [
@@ -437,6 +440,7 @@ public function testActionExecutedWithRecipientFromStoreData(): void
                 'subject' => null,
                 'mediaIds' => [],
                 'senderName' => null,
+                'languageId' => $languageId,
                 'attachmentsConfig' => new MailAttachmentsConfig(
                     Context::createDefaultContext(),
                     $this->mailTemplate,
@@ -467,6 +471,7 @@ public function testActionExecutedWithRecipientFromStoreData(): void
         $flow->setData(MailAware::MAIL_STRUCT, $templateData);
         $flow->setData(MailAware::SALES_CHANNEL_ID, TestDefaults::SALES_CHANNEL);
         $flow->setData(OrderAware::ORDER_ID, $orderId);
+        $flow->setData(LanguageAware::LANGUAGE_ID, $languageId);
         $flow->setData(FlowMailVariables::CONTACT_FORM_DATA, [
             'email' => 'customer@example.com',
             'firstName' => 'Max',
@@ -506,6 +511,7 @@ public function testActionExecutedWithRecipientFromStoreData(): void
                         'firstName' => 'Max',
                         'lastName' => 'Mustermann',
                     ],
+                    'languageId' => $languageId,
                 ]
             );
 
diff --git a/tests/unit/Core/Content/Flow/Dispatching/Storer/LanguageStorerTest.php b/tests/unit/Core/Content/Flow/Dispatching/Storer/LanguageStorerTest.php
new file mode 100644
index 00000000000..3d8be9e14d1
--- /dev/null
+++ b/tests/unit/Core/Content/Flow/Dispatching/Storer/LanguageStorerTest.php
@@ -0,0 +1,122 @@
+<?php declare(strict_types=1);
+
+namespace Shopware\Tests\Unit\Core\Content\Flow\Dispatching\Storer;
+
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\TestCase;
+use Shopware\Core\Content\Flow\Dispatching\StorableFlow;
+use Shopware\Core\Content\Flow\Dispatching\Storer\LanguageStorer;
+use Shopware\Core\Framework\Context;
+use Shopware\Core\Framework\Event\FlowEventAware;
+use Shopware\Core\Framework\Event\LanguageAware;
+use Shopware\Core\Framework\Log\Package;
+use Shopware\Core\Framework\Uuid\Uuid;
+use Shopware\Tests\Unit\Core\Content\Flow\Dispatching\Storer\Stub\LanguageAwareEvent;
+use Shopware\Tests\Unit\Core\Content\Flow\Dispatching\Storer\Stub\NonLanguageAwareEvent;
+
+/**
+ * @internal
+ */
+#[Package('services-settings')]
+#[CoversClass(LanguageStorer::class)]
+class LanguageStorerTest extends TestCase
+{
+    /**
+     * @param array<string, mixed> $stored
+     * @param array<string, mixed> $expected
+     */
+    #[DataProvider('storeDataProvider')]
+    public function testStore(FlowEventAware $event, array $stored, array $expected): void
+    {
+        $storer = new LanguageStorer();
+        $stored = $storer->store($event, $stored);
+
+        static::assertSame($expected, $stored);
+    }
+
+    public static function storeDataProvider(): \Generator
+    {
+        $languageId = Uuid::randomHex();
+
+        yield 'store null' => [
+            'event' => new LanguageAwareEvent(null),
+            'stored' => [],
+            'expected' => [LanguageAware::LANGUAGE_ID => null],
+        ];
+
+        yield 'store id' => [
+            'event' => new LanguageAwareEvent($languageId),
+            'stored' => [],
+            'expected' => [LanguageAware::LANGUAGE_ID => $languageId],
+        ];
+
+        yield 'store existing' => [
+            'event' => new LanguageAwareEvent($languageId),
+            'stored' => ['message' => 'hi'],
+            'expected' => ['message' => 'hi', LanguageAware::LANGUAGE_ID => $languageId],
+        ];
+
+        yield 'store null with existing' => [
+            'event' => new LanguageAwareEvent(null),
+            'stored' => ['message' => 'hi'],
+            'expected' => ['message' => 'hi', LanguageAware::LANGUAGE_ID => null],
+        ];
+
+        yield 'store non language aware' => [
+            'event' => new NonLanguageAwareEvent(),
+            'stored' => [],
+            'expected' => [],
+        ];
+
+        yield 'store non language aware with existing' => [
+            'event' => new NonLanguageAwareEvent(),
+            'stored' => ['message' => 'hi'],
+            'expected' => ['message' => 'hi'],
+        ];
+
+        $languageId2 = Uuid::randomHex();
+
+        yield 'store overwrite' => [
+            'event' => new LanguageAwareEvent($languageId2),
+            'stored' => ['message' => 'hi', LanguageAware::LANGUAGE_ID => $languageId],
+            'expected' => ['message' => 'hi', LanguageAware::LANGUAGE_ID => $languageId2],
+        ];
+    }
+
+    /**
+     * @param array<string, mixed> $expected
+     */
+    #[DataProvider('restoreDataProvider')]
+    public function testRestore(StorableFlow $flow, array $expected): void
+    {
+        $storer = new LanguageStorer();
+        $storer->restore($flow);
+
+        static::assertSame($expected, $flow->data());
+    }
+
+    public static function restoreDataProvider(): \Generator
+    {
+        $languageId = Uuid::randomHex();
+
+        yield 'restore empty' => [
+            'flow' => new StorableFlow('foo', Context::createDefaultContext(), []),
+            'expected' => [],
+        ];
+
+        yield 'restore id' => [
+            'flow' => new StorableFlow('foo', Context::createDefaultContext(), [
+                LanguageAware::LANGUAGE_ID => $languageId,
+            ]),
+            'expected' => [LanguageAware::LANGUAGE_ID => $languageId],
+        ];
+
+        yield 'restore null' => [
+            'flow' => new StorableFlow('foo', Context::createDefaultContext(), [
+                LanguageAware::LANGUAGE_ID => null,
+            ]),
+            'expected' => [LanguageAware::LANGUAGE_ID => null],
+        ];
+    }
+}
diff --git a/tests/unit/Core/Content/Flow/Dispatching/Storer/Stub/LanguageAwareEvent.php b/tests/unit/Core/Content/Flow/Dispatching/Storer/Stub/LanguageAwareEvent.php
new file mode 100644
index 00000000000..b671c9a7d8a
--- /dev/null
+++ b/tests/unit/Core/Content/Flow/Dispatching/Storer/Stub/LanguageAwareEvent.php
@@ -0,0 +1,40 @@
+<?php declare(strict_types=1);
+
+namespace Shopware\Tests\Unit\Core\Content\Flow\Dispatching\Storer\Stub;
+
+use Shopware\Core\Framework\Context;
+use Shopware\Core\Framework\Event\EventData\EventDataCollection;
+use Shopware\Core\Framework\Event\EventData\ScalarValueType;
+use Shopware\Core\Framework\Event\FlowEventAware;
+use Shopware\Core\Framework\Event\LanguageAware;
+
+/**
+ * @internal
+ */
+class LanguageAwareEvent implements FlowEventAware, LanguageAware
+{
+    public function __construct(private readonly ?string $languageId)
+    {
+    }
+
+    public function getName(): string
+    {
+        return 'test';
+    }
+
+    public function getContext(): Context
+    {
+        return Context::createDefaultContext();
+    }
+
+    public static function getAvailableData(): EventDataCollection
+    {
+        return (new EventDataCollection())
+            ->add('languageId', new ScalarValueType(ScalarValueType::TYPE_STRING));
+    }
+
+    public function getLanguageId(): ?string
+    {
+        return $this->languageId;
+    }
+}
diff --git a/tests/unit/Core/Content/Flow/Dispatching/Storer/Stub/NonLanguageAwareEvent.php b/tests/unit/Core/Content/Flow/Dispatching/Storer/Stub/NonLanguageAwareEvent.php
new file mode 100644
index 00000000000..0f857476704
--- /dev/null
+++ b/tests/unit/Core/Content/Flow/Dispatching/Storer/Stub/NonLanguageAwareEvent.php
@@ -0,0 +1,28 @@
+<?php declare(strict_types=1);
+
+namespace Shopware\Tests\Unit\Core\Content\Flow\Dispatching\Storer\Stub;
+
+use Shopware\Core\Framework\Context;
+use Shopware\Core\Framework\Event\EventData\EventDataCollection;
+use Shopware\Core\Framework\Event\FlowEventAware;
+
+/**
+ * @internal
+ */
+class NonLanguageAwareEvent implements FlowEventAware
+{
+    public function getName(): string
+    {
+        return 'test';
+    }
+
+    public function getContext(): Context
+    {
+        return Context::createDefaultContext();
+    }
+
+    public static function getAvailableData(): EventDataCollection
+    {
+        return new EventDataCollection();
+    }
+}