diff --git a/config/packages/zenstruck_schedule.yaml b/config/packages/zenstruck_schedule.yaml
index 06c4840d..6699378a 100644
--- a/config/packages/zenstruck_schedule.yaml
+++ b/config/packages/zenstruck_schedule.yaml
@@ -29,6 +29,10 @@ zenstruck_schedule:
       frequency: "45 1 * * *"
       description: "Removes expired pending newsletter double opt-in requests"
 
+    - task: app:cleanup:travel-mailing-lists
+      frequency: "50 1 * * *"
+      description: "Deletes Mailjet travel mailing lists and their orphaned contacts 30 days after the travel started"
+
     - task: league:oauth2-server:clear-expired-tokens
       frequency: "0 * * * *"
       description: "Removes expired oauth2 tokens hourly"
diff --git a/migrations/Version20261104142531.php b/migrations/Version20261104142531.php
new file mode 100644
index 00000000..16a27f4c
--- /dev/null
+++ b/migrations/Version20261104142531.php
@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+final class Version20261104142531 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return 'Adds travel_mailing_list to track the Mailjet contact lists created per travel until their deletion.';
+    }
+
+    public function up(Schema $schema): void
+    {
+        $this->addSql('CREATE TABLE travel_mailing_list (id INT AUTO_INCREMENT NOT NULL, travel_code VARCHAR(32) NOT NULL, mailjet_list_id INT NOT NULL, delete_after DATETIME NOT NULL COMMENT \'(DC2Type:datetime_immutable)\', created_at DATETIME NOT NULL COMMENT \'(DC2Type:datetime_immutable)\', UNIQUE INDEX UNIQ_68DC6E28BC4DD335 (travel_code), PRIMARY KEY(id)) DEFAULT CHARACTER SET utf8mb4 COLLATE `utf8mb4_unicode_ci` ENGINE = InnoDB');
+    }
+
+    public function down(Schema $schema): void
+    {
+        $this->addSql('DROP TABLE travel_mailing_list');
+    }
+}
diff --git a/src/Command/CleanupTravelMailingListsCommand.php b/src/Command/CleanupTravelMailingListsCommand.php
new file mode 100644
index 00000000..4adc377c
--- /dev/null
+++ b/src/Command/CleanupTravelMailingListsCommand.php
@@ -0,0 +1,67 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Command;
+
+use App\Exception\NewsletterProviderException;
+use App\Repository\TravelMailingListRepository;
+use App\Service\TravelMailingListManager;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\Console\Attribute\AsCommand;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+
+#[AsCommand(
+    name: 'app:cleanup:travel-mailing-lists',
+    description: 'Deletes travel mailing lists and their orphaned contacts from Mailjet 30 days after the travel started',
+)]
+class CleanupTravelMailingListsCommand extends Command
+{
+    public function __construct(
+        private readonly TravelMailingListRepository $travelMailingListRepository,
+        private readonly TravelMailingListManager $travelMailingListManager,
+        private readonly LoggerInterface $logger,
+    ) {
+        parent::__construct();
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $io = new SymfonyStyle($input, $output);
+
+        $mailingLists = $this->travelMailingListRepository->findDueForDeletion(new \DateTimeImmutable());
+        if ([] === $mailingLists) {
+            $io->success('No travel mailing lists due for deletion.');
+
+            return Command::SUCCESS;
+        }
+
+        $failed = 0;
+        foreach ($mailingLists as $mailingList) {
+            try {
+                $deletedContacts = $this->travelMailingListManager->delete($mailingList);
+                $io->writeln(sprintf('Deleted %s (list %d) and %d orphaned contact(s).', $mailingList->getTravelCode(), $mailingList->getMailjetListId(), $deletedContacts));
+            } catch (NewsletterProviderException $exception) {
+                // The row stays, so the next run picks the list up again.
+                ++$failed;
+                $this->logger->error('Delete travel mailing list failed', [
+                    'travel_code' => $mailingList->getTravelCode(),
+                    'mailjet_list_id' => $mailingList->getMailjetListId(),
+                    'error' => $exception->getMessage(),
+                ]);
+                $io->error(sprintf('%s (list %d): %s', $mailingList->getTravelCode(), $mailingList->getMailjetListId(), $exception->getMessage()));
+            }
+        }
+
+        if ($failed > 0) {
+            return Command::FAILURE;
+        }
+
+        $io->success(sprintf('Deleted %d travel mailing list(s).', count($mailingLists)));
+
+        return Command::SUCCESS;
+    }
+}
diff --git a/src/Controller/Admin/TravelMailing/CreateListController.php b/src/Controller/Admin/TravelMailing/CreateListController.php
new file mode 100644
index 00000000..21611d8f
--- /dev/null
+++ b/src/Controller/Admin/TravelMailing/CreateListController.php
@@ -0,0 +1,94 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Controller\Admin\TravelMailing;
+
+use App\BpnConnect\Exception\BpnConnectException;
+use App\BpnConnect\TravelsClient;
+use App\BusProNet\Utility\DateCodeUtility;
+use App\Exception\NewsletterProviderException;
+use App\Repository\TravelMailingListRepository;
+use App\Service\TravelDataProvider;
+use App\Service\TravelMailingListManager;
+use Psr\Log\LoggerInterface;
+use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\Routing\Attribute\Route;
+use Symfony\Component\Security\Http\Attribute\IsGranted;
+
+#[IsGranted('ROLE_CUSTOMER_EXPERT')]
+class CreateListController extends AbstractController
+{
+    public const string CSRF_TOKEN_ID = 'create_travel_mailing_list';
+
+    public function __construct(
+        private readonly TravelsClient $travelsClient,
+        private readonly TravelDataProvider $travelDataProvider,
+        private readonly TravelMailingListRepository $travelMailingListRepository,
+        private readonly TravelMailingListManager $travelMailingListManager,
+        private readonly LoggerInterface $adminLogger,
+    ) {
+    }
+
+    #[Route('/admin/travel-mailing/list', name: 'app_admin_travelmailing_createlist', methods: ['POST'])]
+    public function index(Request $request): Response
+    {
+        if (!$this->isCsrfTokenValid(self::CSRF_TOKEN_ID, $request->request->getString('_token'))) {
+            throw $this->createAccessDeniedException('Invalid CSRF token.');
+        }
+
+        $travelCode = (new DateCodeUtility())->sanitize($request->request->getString('travelCode'));
+        $returnUrl = $this->generateUrl('app_admin_travelmailing', ['travelCode' => $travelCode]);
+
+        if (null !== $this->travelMailingListRepository->findOneByTravelCode($travelCode)) {
+            $this->addFlash('error', sprintf('Für %s gibt es bereits eine Mailjet-Liste.', $travelCode));
+
+            return $this->redirect($returnUrl);
+        }
+
+        $travelStartsAt = $this->travelDataProvider->mapDateCodeToStartDate($travelCode);
+        if (null === $travelStartsAt) {
+            $this->addFlash('error', sprintf('Für %s ist kein Reisebeginn bekannt, die Liste könnte nicht automatisch gelöscht werden.', $travelCode));
+
+            return $this->redirect($returnUrl);
+        }
+
+        // Fetched again rather than posted from the page, so the list holds what BusPro reports now.
+        try {
+            $recipients = $this->travelsClient->getMailingRecipients($travelCode)->data;
+        } catch (BpnConnectException) {
+            $this->addFlash('error', 'Die Teilnehmerliste konnte nicht von BusPro abgerufen werden. Bitte später erneut versuchen.');
+
+            return $this->redirect($returnUrl);
+        }
+
+        if ([] === $recipients) {
+            $this->addFlash('error', sprintf('Keine Empfänger für %s gefunden.', $travelCode));
+
+            return $this->redirect($returnUrl);
+        }
+
+        try {
+            $mailingList = $this->travelMailingListManager->create($travelCode, $recipients, $travelStartsAt);
+        } catch (NewsletterProviderException $exception) {
+            $this->adminLogger->error('Create travel mailing list failed', [
+                'travel_code' => $travelCode,
+                'error' => $exception->getMessage(),
+            ]);
+            $this->addFlash('error', 'Die Mailjet-Liste konnte nicht angelegt werden: '.$exception->getMessage());
+
+            return $this->redirect($returnUrl);
+        }
+
+        $this->adminLogger->info('Create travel mailing list', [
+            'travel_code' => $travelCode,
+            'mailjet_list_id' => $mailingList->getMailjetListId(),
+            'recipients' => count($recipients),
+        ]);
+        $this->addFlash('success', sprintf('Die Mailjet-Liste %s wurde mit %d Empfängern angelegt.', $travelCode, count($recipients)));
+
+        return $this->redirect($returnUrl);
+    }
+}
diff --git a/src/Controller/Admin/TravelMailing/IndexController.php b/src/Controller/Admin/TravelMailing/IndexController.php
index 34894c80..eec53f3a 100644
--- a/src/Controller/Admin/TravelMailing/IndexController.php
+++ b/src/Controller/Admin/TravelMailing/IndexController.php
@@ -9,6 +9,7 @@ use App\BpnConnect\TravelsClient;
 use App\BusProNet\Utility\DateCodeUtility;
 use App\Form\Admin\TravelMailingLookupType;
 use App\Form\Model\TravelMailingLookupDto;
+use App\Repository\TravelMailingListRepository;
 use App\Service\TravelDataProvider;
 use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
 use Symfony\Component\HttpFoundation\Request;
@@ -22,6 +23,7 @@ class IndexController extends AbstractController
     public function __construct(
         private readonly TravelsClient $travelsClient,
         private readonly TravelDataProvider $travelDataProvider,
+        private readonly TravelMailingListRepository $travelMailingListRepository,
     ) {
     }
 
@@ -36,6 +38,8 @@ class IndexController extends AbstractController
 
         $result = null;
         $travelLabel = null;
+        $travelStartsAt = null;
+        $mailingList = null;
         $failed = false;
         if ($form->isSubmitted() && $form->isValid()) {
             // The local index matches codes exactly, so "lpjmp-281126" has to become "LPJMP281126"
@@ -45,6 +49,8 @@ class IndexController extends AbstractController
             try {
                 $result = $this->travelsClient->getMailingRecipients($travelCode);
                 $travelLabel = $this->travelDataProvider->mapDateCodeToLabel($travelCode);
+                $travelStartsAt = $this->travelDataProvider->mapDateCodeToStartDate($travelCode);
+                $mailingList = $this->travelMailingListRepository->findOneByTravelCode($travelCode);
             } catch (BpnConnectException) {
                 // The client has already logged the cause; the page only needs to say it failed.
                 $failed = true;
@@ -55,6 +61,8 @@ class IndexController extends AbstractController
             'form' => $form,
             'result' => $result,
             'travel_label' => $travelLabel,
+            'travel_starts_at' => $travelStartsAt,
+            'mailing_list' => $mailingList,
             'failed' => $failed,
         ]);
     }
diff --git a/src/Entity/TravelMailingList.php b/src/Entity/TravelMailingList.php
new file mode 100644
index 00000000..b8afcb8d
--- /dev/null
+++ b/src/Entity/TravelMailingList.php
@@ -0,0 +1,66 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Entity;
+
+use App\Repository\TravelMailingListRepository;
+use Doctrine\ORM\Mapping as ORM;
+
+/**
+ * A Mailjet contact list created for one travel's participants. The row exists so the list can
+ * be deleted again once the travel is past; the list itself is never updated after creation.
+ */
+#[ORM\Entity(repositoryClass: TravelMailingListRepository::class)]
+class TravelMailingList
+{
+    #[ORM\Id]
+    #[ORM\GeneratedValue]
+    #[ORM\Column(type: 'integer')]
+    private ?int $id = null;
+
+    #[ORM\Column(type: 'string', length: 32, unique: true)]
+    private string $travelCode;
+
+    #[ORM\Column(type: 'integer')]
+    private int $mailjetListId;
+
+    #[ORM\Column(type: 'datetime_immutable')]
+    private \DateTimeImmutable $deleteAfter;
+
+    #[ORM\Column(type: 'datetime_immutable')]
+    private \DateTimeImmutable $createdAt;
+
+    public function __construct(string $travelCode, int $mailjetListId, \DateTimeImmutable $deleteAfter)
+    {
+        $this->travelCode = $travelCode;
+        $this->mailjetListId = $mailjetListId;
+        $this->deleteAfter = $deleteAfter;
+        $this->createdAt = new \DateTimeImmutable();
+    }
+
+    public function getId(): ?int
+    {
+        return $this->id;
+    }
+
+    public function getTravelCode(): string
+    {
+        return $this->travelCode;
+    }
+
+    public function getMailjetListId(): int
+    {
+        return $this->mailjetListId;
+    }
+
+    public function getDeleteAfter(): \DateTimeImmutable
+    {
+        return $this->deleteAfter;
+    }
+
+    public function getCreatedAt(): \DateTimeImmutable
+    {
+        return $this->createdAt;
+    }
+}
diff --git a/src/Mailjet/ApiClient.php b/src/Mailjet/ApiClient.php
index 6f8e6182..9013e405 100644
--- a/src/Mailjet/ApiClient.php
+++ b/src/Mailjet/ApiClient.php
@@ -12,6 +12,7 @@ class ApiClient
 {
     private const string DEFAULT_BASE_URL = 'https://api.mailjet.com/v3/REST';
     private const int NAME_MAX_LENGTH = 255;
+    private const int PAGE_LIMIT = 1000;
 
     /**
      * @param array{firstName?: string, lastName?: string} $contactMetadataFields
@@ -141,6 +142,139 @@ class ApiClient
         ]);
     }
 
+    public function createContactsList(string $name): int
+    {
+        $this->assertConfigured();
+
+        $response = $this->request('POST', 'contactslist', [
+            'json' => [
+                'Name' => $name,
+            ],
+        ]);
+
+        $listId = $response['Data'][0]['ID'] ?? null;
+        if (null === $listId) {
+            throw new NewsletterProviderException(sprintf('Mailjet did not return an id for the new contact list %s', $name));
+        }
+
+        return (int) $listId;
+    }
+
+    /**
+     * Adds the contacts as subscribed, including any who unsubscribed from this list before.
+     * Mailjet processes the request as an asynchronous job.
+     *
+     * @param list<array{email: string, firstName: ?string}> $contacts
+     *
+     * @return int|null the job id
+     */
+    public function addContactsToList(int $listId, array $contacts): ?int
+    {
+        $this->assertConfigured();
+
+        $payload = [];
+        foreach ($contacts as $contact) {
+            $entry = ['Email' => $this->normalizeEmail($contact['email'])];
+
+            $firstName = $this->normalizeName($contact['firstName']);
+            if (null !== $firstName && true === isset($this->contactMetadataFields['firstName'])) {
+                $entry['Properties'] = [$this->contactMetadataFields['firstName'] => $firstName];
+            }
+
+            $payload[] = $entry;
+        }
+
+        $response = $this->request('POST', sprintf('contactslist/%d/managemanycontacts', $listId), [
+            'json' => [
+                'Action' => 'addforce',
+                'Contacts' => $payload,
+            ],
+        ]);
+
+        $jobId = $response['Data'][0]['JobID'] ?? null;
+
+        return null !== $jobId ? (int) $jobId : null;
+    }
+
+    /**
+     * @return list<int>
+     */
+    public function getListContactIds(int $listId): array
+    {
+        $this->assertConfigured();
+
+        $contactIds = [];
+        $offset = 0;
+        do {
+            $response = $this->request('GET', 'listrecipient', [
+                'query' => [
+                    'ContactsList' => $listId,
+                    'Limit' => self::PAGE_LIMIT,
+                    'Offset' => $offset,
+                ],
+            ]);
+
+            $entries = true === is_array($response['Data'] ?? null) ? $response['Data'] : [];
+            foreach ($entries as $entry) {
+                if (true === is_array($entry) && true === isset($entry['ContactID'])) {
+                    $contactIds[] = (int) $entry['ContactID'];
+                }
+            }
+
+            $offset += self::PAGE_LIMIT;
+        } while (self::PAGE_LIMIT === count($entries));
+
+        return array_values(array_unique($contactIds));
+    }
+
+    /**
+     * Lists the contact is on, subscribed or not. Mailjet includes lists deleted within the last 60 days.
+     *
+     * @return list<int>
+     */
+    public function getContactListIds(int $contactId): array
+    {
+        $this->assertConfigured();
+
+        $response = $this->request('GET', sprintf('contact/%d/getcontactslists', $contactId), [
+            'allow_404' => true,
+        ]);
+
+        $listIds = [];
+        foreach ($response['Data'] ?? [] as $entry) {
+            if (true === is_array($entry) && true === isset($entry['ListID'])) {
+                $listIds[] = (int) $entry['ListID'];
+            }
+        }
+
+        return $listIds;
+    }
+
+    public function deleteContactsList(int $listId): void
+    {
+        $this->assertConfigured();
+
+        $this->request('DELETE', sprintf('contactslist/%d', $listId), [
+            'allow_404' => true,
+            'allow_empty' => true,
+        ]);
+    }
+
+    /**
+     * GDPR deletion: Mailjet anonymises the contact immediately and purges it after 30 days.
+     * This cannot be undone.
+     */
+    public function deleteContact(int $contactId): void
+    {
+        $this->assertConfigured();
+
+        $this->request('DELETE', sprintf('contacts/%d', $contactId), [
+            'allow_404' => true,
+            'allow_empty' => true,
+            'api_version' => 'v4',
+        ]);
+    }
+
     private function findOrCreateContactId(string $email): int
     {
         $contactId = $this->resolveContactId($email);
@@ -246,15 +380,17 @@ class ApiClient
     {
         $allow404 = true === ($options['allow_404'] ?? false);
         $allowEmpty = true === ($options['allow_empty'] ?? false);
+        $baseUrl = 'v4' === ($options['api_version'] ?? null) ? $this->getV4BaseUrl() : $this->getBaseUrl();
         unset($options['allow_404']);
         unset($options['allow_empty']);
+        unset($options['api_version']);
 
         $resourcePath = trim($resource, '/');
 
         try {
             $response = $this->httpClient->request(
                 $method,
-                sprintf('%s/%s', $this->getBaseUrl(), $resourcePath),
+                sprintf('%s/%s', $baseUrl, $resourcePath),
                 array_merge($options, [
                     'auth_basic' => sprintf('%s:%s', $this->apiKey, $this->apiSecret),
                 ])
@@ -310,6 +446,16 @@ class ApiClient
         return rtrim($baseUrl, '/');
     }
 
+    /**
+     * The configured base URL points at v3 (`…/v3/REST`); the v4 API sits beside it on the same host.
+     */
+    private function getV4BaseUrl(): string
+    {
+        $baseUrl = preg_replace('~/v3/REST$~i', '', $this->getBaseUrl());
+
+        return sprintf('%s/v4', $baseUrl);
+    }
+
     private function assertConfigured(): void
     {
         if (true === empty($this->apiKey) || true === empty($this->apiSecret)) {
diff --git a/src/Repository/TravelMailingListRepository.php b/src/Repository/TravelMailingListRepository.php
new file mode 100644
index 00000000..69f839bd
--- /dev/null
+++ b/src/Repository/TravelMailingListRepository.php
@@ -0,0 +1,38 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Repository;
+
+use App\Entity\TravelMailingList;
+use Doctrine\Bundle\DoctrineBundle\Repository\ServiceEntityRepository;
+use Doctrine\Persistence\ManagerRegistry;
+
+/**
+ * @extends ServiceEntityRepository<TravelMailingList>
+ */
+class TravelMailingListRepository extends ServiceEntityRepository
+{
+    public function __construct(ManagerRegistry $registry)
+    {
+        parent::__construct($registry, TravelMailingList::class);
+    }
+
+    public function findOneByTravelCode(string $travelCode): ?TravelMailingList
+    {
+        return $this->findOneBy(['travelCode' => $travelCode]);
+    }
+
+    /**
+     * @return list<TravelMailingList>
+     */
+    public function findDueForDeletion(\DateTimeImmutable $now): array
+    {
+        return $this->createQueryBuilder('l')
+            ->where('l.deleteAfter <= :now')
+            ->setParameter('now', $now)
+            ->orderBy('l.deleteAfter', 'ASC')
+            ->getQuery()
+            ->getResult();
+    }
+}
diff --git a/src/Service/TravelDataProvider.php b/src/Service/TravelDataProvider.php
index 4e80237c..8e4fd684 100644
--- a/src/Service/TravelDataProvider.php
+++ b/src/Service/TravelDataProvider.php
@@ -432,6 +432,18 @@ class TravelDataProvider
         return $this->travelLookupService->mapDateCodeToLabel($dateCode);
     }
 
+    /**
+     * Map date code to the travel's start date.
+     *
+     * @param string $dateCode The date code to map
+     *
+     * @return \DateTimeImmutable|null The start date or null if not found
+     */
+    public function mapDateCodeToStartDate(string $dateCode): ?\DateTimeImmutable
+    {
+        return $this->travelLookupService->mapDateCodeToStartDate($dateCode);
+    }
+
     /**
      * Map hotel code to hotel ID.
      *
diff --git a/src/Service/TravelIndex.php b/src/Service/TravelIndex.php
index 2cf4f018..3958856f 100644
--- a/src/Service/TravelIndex.php
+++ b/src/Service/TravelIndex.php
@@ -127,6 +127,26 @@ class TravelIndex
         return $this->generateFilesMap()[$dateId]['label'] ?? null;
     }
 
+    /**
+     * Resolve a date code to the travel's start date.
+     *
+     * @param string $dateCode The date code to resolve
+     *
+     * @return \DateTimeImmutable|null The start date, or null if the code is not found or the travel has none
+     */
+    public function mapDateCodeToStartDate(string $dateCode): ?\DateTimeImmutable
+    {
+        $dateId = $this->mapDateCodeToId($dateCode);
+
+        if (null === $dateId) {
+            return null;
+        }
+
+        $dateFrom = $this->generateFilesMap()[$dateId]['dateFrom'] ?? null;
+
+        return $dateFrom instanceof \DateTimeImmutable ? $dateFrom : null;
+    }
+
     /**
      * Convert a hotel code string to its corresponding hotel ID.
      *
diff --git a/src/Service/TravelMailingListManager.php b/src/Service/TravelMailingListManager.php
new file mode 100644
index 00000000..8849f5c4
--- /dev/null
+++ b/src/Service/TravelMailingListManager.php
@@ -0,0 +1,142 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Service;
+
+use App\BpnConnect\Model\TravelMailingRecipient;
+use App\Entity\TravelMailingList;
+use App\Exception\NewsletterProviderException;
+use App\Mailjet\ApiClient;
+use Doctrine\ORM\EntityManagerInterface;
+use Psr\Log\LoggerInterface;
+
+/**
+ * Creates one Mailjet contact list per travel and deletes it again 30 days after the travel
+ * started, together with every contact that is on no other Mailjet list.
+ */
+class TravelMailingListManager
+{
+    private const string DELETE_AFTER = '+30 days';
+
+    public function __construct(
+        private readonly ApiClient $mailjet,
+        private readonly EntityManagerInterface $entityManager,
+        private readonly LoggerInterface $logger,
+    ) {
+    }
+
+    /**
+     * @param TravelMailingRecipient[] $recipients
+     *
+     * @throws NewsletterProviderException
+     */
+    public function create(string $travelCode, array $recipients, \DateTimeImmutable $travelStartsAt): TravelMailingList
+    {
+        $listId = $this->mailjet->createContactsList($travelCode);
+
+        // Tracked before the contacts go in, so a list Mailjet already holds is never left without a row
+        // that the cleanup would find.
+        $mailingList = new TravelMailingList($travelCode, $listId, $travelStartsAt->modify(self::DELETE_AFTER));
+        $this->entityManager->persist($mailingList);
+        $this->entityManager->flush();
+
+        try {
+            $jobId = $this->mailjet->addContactsToList($listId, $this->buildContacts($recipients));
+        } catch (NewsletterProviderException $exception) {
+            $this->discardEmptyList($mailingList);
+
+            throw $exception;
+        }
+
+        $this->logger->info('Created Mailjet travel mailing list', [
+            'travel_code' => $travelCode,
+            'mailjet_list_id' => $listId,
+            'mailjet_job_id' => $jobId,
+            'recipients' => count($recipients),
+        ]);
+
+        return $mailingList;
+    }
+
+    /**
+     * Deletes the orphaned contacts first and the list last, so a run that fails halfway can be
+     * repeated: the list still names whoever is left.
+     *
+     * @return int the number of contacts deleted
+     *
+     * @throws NewsletterProviderException
+     */
+    public function delete(TravelMailingList $mailingList): int
+    {
+        $listId = $mailingList->getMailjetListId();
+
+        $deletedContacts = 0;
+        foreach ($this->mailjet->getListContactIds($listId) as $contactId) {
+            // Anyone who is, or recently was, on another list is kept: their newsletter consent or
+            // another travel's mailing still needs the contact.
+            if ([$listId] !== array_values(array_unique($this->mailjet->getContactListIds($contactId)))) {
+                continue;
+            }
+
+            $this->mailjet->deleteContact($contactId);
+            ++$deletedContacts;
+        }
+
+        $this->mailjet->deleteContactsList($listId);
+
+        $this->entityManager->remove($mailingList);
+        $this->entityManager->flush();
+
+        $this->logger->info('Deleted Mailjet travel mailing list', [
+            'travel_code' => $mailingList->getTravelCode(),
+            'mailjet_list_id' => $listId,
+            'deleted_contacts' => $deletedContacts,
+        ]);
+
+        return $deletedContacts;
+    }
+
+    /**
+     * @param TravelMailingRecipient[] $recipients
+     *
+     * @return list<array{email: string, firstName: ?string}>
+     */
+    private function buildContacts(array $recipients): array
+    {
+        // Several participants can share one address; the first name that comes with it wins.
+        $contacts = [];
+        foreach ($recipients as $recipient) {
+            $email = mb_strtolower(trim($recipient->email));
+            if ('' === $email || true === isset($contacts[$email])) {
+                continue;
+            }
+
+            $contacts[$email] = [
+                'email' => $email,
+                'firstName' => '' !== trim($recipient->firstName) ? $recipient->firstName : null,
+            ];
+        }
+
+        return array_values($contacts);
+    }
+
+    private function discardEmptyList(TravelMailingList $mailingList): void
+    {
+        try {
+            $this->mailjet->deleteContactsList($mailingList->getMailjetListId());
+        } catch (NewsletterProviderException $exception) {
+            // The row stays, so the scheduled cleanup removes the list later.
+            $this->logger->error('Could not delete Mailjet travel mailing list after a failed import', [
+                'travel_code' => $mailingList->getTravelCode(),
+                'mailjet_list_id' => $mailingList->getMailjetListId(),
+                'error' => $exception->getMessage(),
+            ]);
+
+            return;
+        }
+
+        $this->entityManager->remove($mailingList);
+        $this->entityManager->flush();
+    }
+}
diff --git a/templates/admin/travel_mailing/index.html.twig b/templates/admin/travel_mailing/index.html.twig
index 5dda24fd..d9fc4b72 100644
--- a/templates/admin/travel_mailing/index.html.twig
+++ b/templates/admin/travel_mailing/index.html.twig
@@ -37,6 +37,31 @@
                     {{ result.data|length }} Empfänger für <code>{{ result.travelCode }}</code>
                 </p>
             </div>
+            <div class="pb-6 text-sm">
+                {% if mailing_list is not null %}
+                    <p>
+                        Mailjet-Liste <code>{{ mailing_list.travelCode }}</code> (ID {{ mailing_list.mailjetListId }})
+                        am {{ mailing_list.createdAt|date('d.m.Y, H:i') }} angelegt,
+                        wird ab {{ mailing_list.deleteAfter|date('d.m.Y') }} automatisch gelöscht.
+                    </p>
+                {% elseif travel_starts_at is null %}
+                    <p class="text-gray-700">
+                        Kein Reisebeginn bekannt, daher kann keine Mailjet-Liste angelegt werden.
+                    </p>
+                {% else %}
+                    <form method="post" action="{{ path('app_admin_travelmailing_createlist') }}">
+                        <input type="hidden" name="travelCode" value="{{ result.travelCode }}">
+                        <input type="hidden" name="_token" value="{{ csrf_token(constant('App\\Controller\\Admin\\TravelMailing\\CreateListController::CSRF_TOKEN_ID')) }}">
+                        <button type="submit" class="button button--primary button--small">
+                            Mailjet-Liste anlegen
+                        </button>
+                        <span class="pl-2 text-gray-700">
+                            Alle Empfänger werden ohne Opt-in eingetragen; die Liste wird 30 Tage nach Reisebeginn
+                            ({{ travel_starts_at|date('d.m.Y') }}) gelöscht.
+                        </span>
+                    </form>
+                {% endif %}
+            </div>
             <div class="data-table-wrapper">
                 <div class="data-table-wrapper__inner text-sm">
                     <table class="data-table">
diff --git a/tests/Mailjet/ApiClientTest.php b/tests/Mailjet/ApiClientTest.php
index 1ea9385c..fd565118 100644
--- a/tests/Mailjet/ApiClientTest.php
+++ b/tests/Mailjet/ApiClientTest.php
@@ -194,4 +194,88 @@ class ApiClientTest extends TestCase
             'Action' => 'addforce',
         ], json_decode((string) $requests[0][2]['body'], true, 512, JSON_THROW_ON_ERROR));
     }
+
+    public function testAddContactsToListForcesSubscriptionAndSendsOnlyTheFirstName(): void
+    {
+        $requests = [];
+        $client = new MockHttpClient(function (string $method, string $url, array $options) use (&$requests): MockResponse {
+            $requests[] = [$method, $url, $options];
+
+            return new MockResponse(json_encode(['Data' => [['JobID' => 555]]], JSON_THROW_ON_ERROR), ['http_code' => 201]);
+        });
+
+        $mailjet = new ApiClient($client, new NullLogger(), 'key', 'secret', 'https://mailjet.test', null, [
+            'firstName' => 'vorname',
+            'lastName' => 'nachname',
+        ]);
+
+        $jobId = $mailjet->addContactsToList(42, [
+            ['email' => ' Mia@Example.COM ', 'firstName' => ' Mia '],
+            ['email' => 'anon@example.com', 'firstName' => null],
+        ]);
+
+        self::assertSame(555, $jobId);
+        self::assertSame('POST', $requests[0][0]);
+        self::assertSame('https://mailjet.test/contactslist/42/managemanycontacts', $requests[0][1]);
+        self::assertSame([
+            'Action' => 'addforce',
+            'Contacts' => [
+                ['Email' => 'mia@example.com', 'Properties' => ['vorname' => 'Mia']],
+                ['Email' => 'anon@example.com'],
+            ],
+        ], json_decode((string) $requests[0][2]['body'], true, 512, JSON_THROW_ON_ERROR));
+    }
+
+    public function testCreateContactsListReturnsTheNewListId(): void
+    {
+        $requests = [];
+        $client = new MockHttpClient(function (string $method, string $url, array $options) use (&$requests): MockResponse {
+            $requests[] = [$method, $url, $options];
+
+            return new MockResponse(json_encode(['Data' => [['ID' => 42, 'Name' => 'LPJMP281126']]], JSON_THROW_ON_ERROR), ['http_code' => 201]);
+        });
+
+        $mailjet = new ApiClient($client, new NullLogger(), 'key', 'secret', 'https://mailjet.test');
+
+        self::assertSame(42, $mailjet->createContactsList('LPJMP281126'));
+        self::assertSame('https://mailjet.test/contactslist', $requests[0][1]);
+        self::assertSame(['Name' => 'LPJMP281126'], json_decode((string) $requests[0][2]['body'], true, 512, JSON_THROW_ON_ERROR));
+    }
+
+    public function testGetListContactIdsPagesThroughAllRecipients(): void
+    {
+        $offsets = [];
+        $client = new MockHttpClient(function (string $method, string $url, array $options) use (&$offsets): MockResponse {
+            $offset = (int) $options['query']['Offset'];
+            $offsets[] = $offset;
+            $data = 0 === $offset
+                ? array_map(static fn (int $id): array => ['ContactID' => $id], range(1, 1000))
+                : [['ContactID' => 1001]];
+
+            return new MockResponse(json_encode(['Data' => $data], JSON_THROW_ON_ERROR));
+        });
+
+        $mailjet = new ApiClient($client, new NullLogger(), 'key', 'secret', 'https://mailjet.test');
+
+        $contactIds = $mailjet->getListContactIds(42);
+
+        self::assertSame([0, 1000], $offsets);
+        self::assertCount(1001, $contactIds);
+    }
+
+    public function testDeleteContactUsesTheV4Api(): void
+    {
+        $requests = [];
+        $client = new MockHttpClient(function (string $method, string $url, array $options) use (&$requests): MockResponse {
+            $requests[] = [$method, $url];
+
+            return new MockResponse('', ['http_code' => 200]);
+        });
+
+        $mailjet = new ApiClient($client, new NullLogger(), 'key', 'secret', 'https://api.mailjet.com/v3/REST');
+
+        $mailjet->deleteContact(99);
+
+        self::assertSame([['DELETE', 'https://api.mailjet.com/v4/contacts/99']], $requests);
+    }
 }
diff --git a/tests/Service/TravelIndexTest.php b/tests/Service/TravelIndexTest.php
index 7967f643..7f18dd25 100644
--- a/tests/Service/TravelIndexTest.php
+++ b/tests/Service/TravelIndexTest.php
@@ -186,6 +186,32 @@ class TravelIndexTest extends TestCase
         $this->assertNull($result);
     }
 
+    // -------------------------------------------------------------------------
+    // mapDateCodeToStartDate
+    // -------------------------------------------------------------------------
+
+    public function testMapDateCodeToStartDateReturnsTheTravelStartDate(): void
+    {
+        $this->travelLoader->method('generateFilesMap')->willReturn([
+            42 => ['id' => 42, 'code' => 'WI25', 'dateFrom' => new \DateTimeImmutable('2026-12-28'), 'hotels' => []],
+        ]);
+        $this->travelSnapshotService->method('generateMapping')->willReturn([]);
+
+        $result = $this->service()->mapDateCodeToStartDate('WI25');
+
+        $this->assertEquals(new \DateTimeImmutable('2026-12-28'), $result);
+    }
+
+    public function testMapDateCodeToStartDateReturnsNullWhenNotFound(): void
+    {
+        $this->travelLoader->method('generateFilesMap')->willReturn([]);
+        $this->travelSnapshotService->method('generateMapping')->willReturn([]);
+
+        $result = $this->service()->mapDateCodeToStartDate('UNKNOWN');
+
+        $this->assertNull($result);
+    }
+
     // -------------------------------------------------------------------------
     // mapHotelCodeToId
     // -------------------------------------------------------------------------
diff --git a/tests/Service/TravelMailingListManagerTest.php b/tests/Service/TravelMailingListManagerTest.php
new file mode 100644
index 00000000..a8daed0d
--- /dev/null
+++ b/tests/Service/TravelMailingListManagerTest.php
@@ -0,0 +1,92 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Tests\Service;
+
+use App\BpnConnect\Model\TravelMailingRecipient;
+use App\Entity\TravelMailingList;
+use App\Exception\NewsletterProviderException;
+use App\Mailjet\ApiClient;
+use App\Service\TravelMailingListManager;
+use Doctrine\ORM\EntityManagerInterface;
+use PHPUnit\Framework\TestCase;
+use Psr\Log\NullLogger;
+
+class TravelMailingListManagerTest extends TestCase
+{
+    public function testCreateTracksTheListAndAddsDeduplicatedContacts(): void
+    {
+        $mailjet = $this->createMock(ApiClient::class);
+        $mailjet->expects(self::once())->method('createContactsList')->with('LPJMP281126')->willReturn(42);
+        $mailjet->expects(self::once())->method('addContactsToList')->with(42, [
+            ['email' => 'mia@example.com', 'firstName' => 'Mia'],
+            ['email' => 'tom@example.com', 'firstName' => null],
+        ])->willReturn(555);
+
+        $entityManager = $this->createMock(EntityManagerInterface::class);
+        $entityManager->expects(self::once())->method('persist')->with(self::isInstanceOf(TravelMailingList::class));
+        $entityManager->expects(self::never())->method('remove');
+
+        $mailingList = (new TravelMailingListManager($mailjet, $entityManager, new NullLogger()))->create('LPJMP281126', [
+            new TravelMailingRecipient('Mia@Example.com', 'Mia', 'Muster'),
+            new TravelMailingRecipient('mia@example.com', 'Lea', 'Muster'),
+            new TravelMailingRecipient('tom@example.com', '', 'Test'),
+        ], new \DateTimeImmutable('2026-11-28'));
+
+        self::assertSame(42, $mailingList->getMailjetListId());
+        self::assertEquals(new \DateTimeImmutable('2026-12-28'), $mailingList->getDeleteAfter());
+    }
+
+    public function testCreateDiscardsTheListWhenTheContactsCannotBeAdded(): void
+    {
+        $mailjet = $this->createMock(ApiClient::class);
+        $mailjet->method('createContactsList')->willReturn(42);
+        $mailjet->method('addContactsToList')->willThrowException(new NewsletterProviderException('boom'));
+        $mailjet->expects(self::once())->method('deleteContactsList')->with(42);
+
+        $entityManager = $this->createMock(EntityManagerInterface::class);
+        $entityManager->expects(self::once())->method('remove')->with(self::isInstanceOf(TravelMailingList::class));
+
+        $this->expectException(NewsletterProviderException::class);
+
+        (new TravelMailingListManager($mailjet, $entityManager, new NullLogger()))->create('LPJMP281126', [
+            new TravelMailingRecipient('mia@example.com', 'Mia', 'Muster'),
+        ], new \DateTimeImmutable('2026-11-28'));
+    }
+
+    public function testDeleteRemovesOnlyContactsOnNoOtherList(): void
+    {
+        $mailjet = $this->createMock(ApiClient::class);
+        $mailjet->method('getListContactIds')->with(42)->willReturn([1, 2]);
+        $mailjet->method('getContactListIds')->willReturnMap([
+            [1, [42]],
+            [2, [42, 10321569]],
+        ]);
+        $mailjet->expects(self::once())->method('deleteContact')->with(1);
+        $mailjet->expects(self::once())->method('deleteContactsList')->with(42);
+
+        $entityManager = $this->createMock(EntityManagerInterface::class);
+        $entityManager->expects(self::once())->method('remove');
+
+        $deleted = (new TravelMailingListManager($mailjet, $entityManager, new NullLogger()))
+            ->delete(new TravelMailingList('LPJMP281126', 42, new \DateTimeImmutable('2026-12-28')));
+
+        self::assertSame(1, $deleted);
+    }
+
+    public function testDeleteKeepsTheRowWhenMailjetFails(): void
+    {
+        $mailjet = $this->createMock(ApiClient::class);
+        $mailjet->method('getListContactIds')->willReturn([]);
+        $mailjet->expects(self::once())->method('deleteContactsList')->willThrowException(new NewsletterProviderException('boom'));
+
+        $entityManager = $this->createMock(EntityManagerInterface::class);
+        $entityManager->expects(self::never())->method('remove');
+
+        $this->expectException(NewsletterProviderException::class);
+
+        (new TravelMailingListManager($mailjet, $entityManager, new NullLogger()))
+            ->delete(new TravelMailingList('LPJMP281126', 42, new \DateTimeImmutable('2026-12-28')));
+    }
+}