diff --git a/lib/Controller/AccountApiController.php b/lib/Controller/AccountApiController.php
index 7fb101d4b1..1e6fd9c0bb 100644
--- a/lib/Controller/AccountApiController.php
+++ b/lib/Controller/AccountApiController.php
@@ -37,9 +37,9 @@ public function __construct(
 	}
 
 	/**
-	 * List all email accounts and their aliases of the user which is currently logged-in.
+	 * List all email accounts and their aliases of the user which is currently logged-in
 	 *
-	 * @return DataResponse<Http::STATUS_OK, MailAccountListResponse, array{}>|DataResponse<Http::STATUS_NOT_FOUND, array{}, array{}>
+	 * @return DataResponse<Http::STATUS_OK, MailAccountListResponse[], array{}>|DataResponse<Http::STATUS_NOT_FOUND, array{}, array{}>
 	 *
 	 * 200: Account list
 	 * 404: User was not logged in
diff --git a/lib/ResponseDefinitions.php b/lib/ResponseDefinitions.php
index c8e3bea835..9dfd9f7418 100644
--- a/lib/ResponseDefinitions.php
+++ b/lib/ResponseDefinitions.php
@@ -48,11 +48,11 @@
  * @psalm-type MailAccountListResponse = array{
  *      id: int,
  *      email: string,
- *      aliases: array {
+ *      aliases: array{
  *          id: int,
  *          email: string,
- *          name?: string,
- *      }
+ *          name: ?string,
+ *      }[]
  *  }
  */
 class ResponseDefinitions {
diff --git a/tests/Unit/Controller/AccountApiControllerTest.php b/tests/Unit/Controller/AccountApiControllerTest.php
new file mode 100644
index 0000000000..c560c8e4f5
--- /dev/null
+++ b/tests/Unit/Controller/AccountApiControllerTest.php
@@ -0,0 +1,168 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace Unit\Controller;
+
+use ChristophWurst\Nextcloud\Testing\TestCase;
+use OCA\Mail\Account;
+use OCA\Mail\Controller\AccountApiController;
+use OCA\Mail\Db\Alias;
+use OCA\Mail\Db\MailAccount;
+use OCA\Mail\Service\AccountService;
+use OCA\Mail\Service\AliasesService;
+use OCP\AppFramework\Http;
+use OCP\IRequest;
+use PHPUnit\Framework\MockObject\MockObject;
+
+class AccountApiControllerTest extends TestCase {
+	private const USER_ID = 'user';
+
+	private AccountApiController $controller;
+
+	private IRequest&MockObject $request;
+	private AccountService&MockObject $accountService;
+	private AliasesService&MockObject $aliasesService;
+
+	protected function setUp(): void {
+		parent::setUp();
+
+		$this->request = $this->createMock(IRequest::class);
+		$this->accountService = $this->createMock(AccountService::class);
+		$this->aliasesService = $this->createMock(AliasesService::class);
+
+		$this->controller = new AccountApiController(
+			'mail',
+			$this->request,
+			self::USER_ID,
+			$this->accountService,
+			$this->aliasesService,
+		);
+	}
+
+	public function testListWithoutUser() {
+		$controller = new AccountApiController(
+			'mail',
+			$this->request,
+			null,
+			$this->accountService,
+			$this->aliasesService,
+		);
+
+		$this->accountService->expects(self::never())
+			->method('findByUserId');
+
+		$this->aliasesService->expects(self::never())
+			->method('findAll');
+
+		$actual = $controller->list();
+		$this->assertEquals(Http::STATUS_NOT_FOUND, $actual->getStatus());
+	}
+
+	public function testList() {
+		$mailAccount = new MailAccount();
+		$mailAccount->setId(42);
+		$mailAccount->setEmail('foo@bar.com');
+
+		$account = new Account($mailAccount);
+		$this->accountService->expects(self::once())
+			->method('findByUserId')
+			->with(self::USER_ID)
+			->willReturn([$account]);
+
+		$alias = new Alias();
+		$alias->setId(10);
+		$alias->setName('Baz');
+		$alias->setAlias('baz@bar.com');
+		$this->aliasesService->expects(self::once())
+			->method('findAll')
+			->with(42, self::USER_ID)
+			->willReturn([$alias]);
+
+		$actual = $this->controller->list();
+		$this->assertEquals(Http::STATUS_OK, $actual->getStatus());
+		$this->assertEquals([
+			[
+				'id' => 42,
+				'email' => 'foo@bar.com',
+				'aliases' => [
+					[
+						'id' => 10,
+						'email' => 'baz@bar.com',
+						'name' => 'Baz',
+					],
+				],
+			]
+		], $actual->getData());
+	}
+
+	public function testListWithAliasWithoutName() {
+		$mailAccount = new MailAccount();
+		$mailAccount->setId(42);
+		$mailAccount->setEmail('foo@bar.com');
+
+		$account = new Account($mailAccount);
+		$this->accountService->expects(self::once())
+			->method('findByUserId')
+			->with(self::USER_ID)
+			->willReturn([$account]);
+
+		$alias = new Alias();
+		$alias->setId(10);
+		$alias->setName(null);
+		$alias->setAlias('baz@bar.com');
+		$this->aliasesService->expects(self::once())
+			->method('findAll')
+			->with(42, self::USER_ID)
+			->willReturn([$alias]);
+
+		$actual = $this->controller->list();
+		$this->assertEquals(Http::STATUS_OK, $actual->getStatus());
+		$this->assertEquals([
+			[
+				'id' => 42,
+				'email' => 'foo@bar.com',
+				'aliases' => [
+					[
+						'id' => 10,
+						'email' => 'baz@bar.com',
+						'name' => null,
+					],
+				],
+			]
+		], $actual->getData());
+	}
+
+	public function testListWithoutAliases() {
+		$mailAccount = new MailAccount();
+		$mailAccount->setId(42);
+		$mailAccount->setEmail('foo@bar.com');
+
+		$account = new Account($mailAccount);
+		$this->accountService->expects(self::once())
+			->method('findByUserId')
+			->with(self::USER_ID)
+			->willReturn([$account]);
+
+		$this->aliasesService->expects(self::once())
+			->method('findAll')
+			->with(42, self::USER_ID)
+			->willReturn([]);
+
+		$actual = $this->controller->list();
+		$this->assertEquals(Http::STATUS_OK, $actual->getStatus());
+		$this->assertEquals([
+			[
+				'id' => 42,
+				'email' => 'foo@bar.com',
+				'aliases' => [],
+			]
+		], $actual->getData());
+	}
+
+}