diff --git a/lib/Controller/DelegationController.php b/lib/Controller/DelegationController.php
index 96b8ab4af1..0a982a4529 100644
--- a/lib/Controller/DelegationController.php
+++ b/lib/Controller/DelegationController.php
@@ -82,7 +82,7 @@ public function delegate(int $accountId, string $userId): JSONResponse {
 		}
 
 		try {
-			$delegation = $this->delegationService->delegate($accountId, $userId);
+			$delegation = $this->delegationService->delegate($account, $userId, $this->currentUserId);
 		} catch (DelegationExistsException) {
 			return new JSONResponse(['message' => 'Delegation already exists'], Http::STATUS_CONFLICT);
 		}
@@ -109,7 +109,7 @@ public function unDelegate(int $accountId, string $userId): JSONResponse {
 			return new JSONResponse([], Http::STATUS_UNAUTHORIZED);
 		}
 
-		$this->delegationService->unDelegate($accountId, $userId);
+		$this->delegationService->unDelegate($account, $userId, $this->currentUserId);
 		return new JSONResponse([], Http::STATUS_OK);
 	}
 }
diff --git a/lib/Notification/Notifier.php b/lib/Notification/Notifier.php
index dedd2e7ebd..b3f2d26b41 100644
--- a/lib/Notification/Notifier.php
+++ b/lib/Notification/Notifier.php
@@ -72,8 +72,57 @@ public function prepare(INotification $notification, string $languageCode): INot
 						]
 					]);
 				break;
+			case 'account_delegation':
+				$parameters = $notification->getSubjectParameters();
+				$messageParameters = $notification->getMessageParameters();
+				$delegated = $messageParameters['delegated'];
+				if ($delegated) {
+					$notification->setRichSubject($l->t('{account_email} has been delegated to you'), [
+						'account_email' => [
+							'type' => 'highlight',
+							'id' => (string)$parameters['id'],
+							'name' => $parameters['account_email']
+						]
+					]);
+					$notification->setRichMessage($l->t('{user} delegated {account} to you'),
+						[
+							'user' => [
+								'type' => 'user',
+								'id' => $messageParameters['current_user_id'],
+								'name' => $messageParameters['current_user_display_name'],
+							],
+							'account' => [
+								'type' => 'highlight',
+								'id' => (string)$messageParameters['id'],
+								'name' => $messageParameters['account_email']
+							]
+						]);
+				} else {
+					$notification->setRichSubject($l->t('{account_email} is no longer delegated to you'), [
+						'account_email' => [
+							'type' => 'highlight',
+							'id' => (string)$parameters['id'],
+							'name' => $parameters['account_email']
+						]
+					]);
+					$notification->setRichMessage($l->t('{user} revoked delagation for {account}'),
+						[
+							'user' => [
+								'type' => 'user',
+								'id' => $messageParameters['current_user_id'],
+								'name' => $messageParameters['current_user_display_name'],
+							],
+							'account' => [
+								'type' => 'highlight',
+								'id' => (string)$messageParameters['id'],
+								'name' => $messageParameters['account_email']
+							]
+						]);
+				}
+
+				break;
 			default:
-				throw  new UnknownNotificationException();
+				throw new UnknownNotificationException();
 		}
 
 		return $notification;
diff --git a/lib/Service/DelegationService.php b/lib/Service/DelegationService.php
index b2e1d9fbde..00050c7d53 100644
--- a/lib/Service/DelegationService.php
+++ b/lib/Service/DelegationService.php
@@ -9,6 +9,7 @@
 
 namespace OCA\Mail\Service;
 
+use OCA\Mail\Account;
 use OCA\Mail\Db\AliasMapper;
 use OCA\Mail\Db\Delegation;
 use OCA\Mail\Db\DelegationMapper;
@@ -18,6 +19,9 @@
 use OCA\Mail\Db\MessageMapper;
 use OCA\Mail\Exception\DelegationExistsException;
 use OCP\AppFramework\Db\DoesNotExistException;
+use OCP\AppFramework\Utility\ITimeFactory;
+use OCP\IUserManager;
+use OCP\Notification\IManager;
 
 class DelegationService {
 
@@ -28,10 +32,14 @@ public function __construct(
 		private MessageMapper $messageMapper,
 		private AliasMapper $aliasMapper,
 		private LocalMessageMapper $localMessageMapper,
+		private IUserManager $userManager,
+		private IManager $notificationManager,
+		private ITimeFactory $time,
 	) {
 	}
 
-	public function delegate(int $accountId, string $userId): Delegation {
+	public function delegate(Account $account, string $userId, string $currentUserId): Delegation {
+		$accountId = $account->getId();
 		try {
 			$this->delegationMapper->find($accountId, $userId);
 			throw new DelegationExistsException("Delegation already exists for account $accountId and user $userId");
@@ -42,7 +50,9 @@ public function delegate(int $accountId, string $userId): Delegation {
 		$delegation = new Delegation();
 		$delegation->setAccountId($accountId);
 		$delegation->setUserId($userId);
-		return $this->delegationMapper->insert($delegation);
+		$result = $this->delegationMapper->insert($delegation);
+		$this->notify($userId, $currentUserId, $account, true);
+		return $result;
 	}
 
 	public function findDelegatedToUsersForAccount(int $accountId): array {
@@ -52,9 +62,11 @@ public function findDelegatedToUsersForAccount(int $accountId): array {
 	/**
 	 * @throws DoesNotExistException
 	 */
-	public function unDelegate(int $accountId, string $userId): void {
+	public function unDelegate(Account $account, string $userId, string $currentUserId): void {
+		$accountId = $account->getId();
 		$delegation = $this->delegationMapper->find($accountId, $userId);
 		$this->delegationMapper->delete($delegation);
+		$this->notify($userId, $currentUserId, $account, false);
 	}
 
 	/**
@@ -103,4 +115,37 @@ public function resolveLocalMessageUserId(int $localMessageId, string $currentUs
 		$accountId = $this->localMessageMapper->findAccountIdForLocalMessage($localMessageId);
 		return $this->resolveAccountUserId($accountId, $currentUserId);
 	}
+
+	/**
+	 * Send a notification on delegation
+	 * @param string $userId The user the account is being delegated to
+	 * @param string $currentUserId Current user
+	 * @param Account $account The delegated account
+	 * @param bool $delegated true for delegate|false for undelegate
+	 * @return void
+	 */
+	private function notify(string $userId, string $currentUserId, Account $account, bool $delegated) {
+		$notification = $this->notificationManager->createNotification();
+		$displayName = $this->userManager->get($currentUserId)->getDisplayName();
+		$time = $this->time->getDateTime('now');
+		$notification
+			->setApp('mail')
+			->setUser($userId)
+			->setObject('delegation', (string)$account->getId())
+			->setSubject('account_delegation', [
+				'id' => $account->getId(),
+				'account_email' => $account->getEmail(),
+
+			])
+			->setDateTime($time)
+			->setMessage('account_delegation_changed', [
+				'id' => $account->getId(),
+				'delegated' => $delegated,
+				'current_user_id' => $currentUserId,
+				'current_user_display_name' => $displayName,
+				'account_email' => $account->getEmail(),
+			]
+			);
+		$this->notificationManager->notify($notification);
+	}
 }