diff --git a/.env b/.env
index 75f4bd79..a6b62db4 100644
--- a/.env
+++ b/.env
@@ -44,6 +44,9 @@ MAILJET_API_KEY=
 MAILJET_API_SECRET=
 MAILJET_API_BASE_URL=https://api.mailjet.com/v3/REST
 MAILJET_DEFAULT_LIST_ID=
+# Sub-account for the travel mailing lists
+MAILJET_TRAVEL_MAILING_API_KEY=
+MAILJET_TRAVEL_MAILING_API_SECRET=
 # Development default for HTTP Basic Auth password; override in production secrets.
 MAILJET_WEBHOOK_BASIC_PASSWORD=secret
 APP_NEWSLETTER_CONFIRMATION_TTL_HOURS=1
diff --git a/config/services.yaml b/config/services.yaml
index de381405..956e9a90 100644
--- a/config/services.yaml
+++ b/config/services.yaml
@@ -441,6 +441,20 @@ services:
             $defaultListId: '%env(default::MAILJET_DEFAULT_LIST_ID)%'
             $contactMetadataFields: '%mailjet_contact_metadata_fields%'
 
+    # Travel mailing lists live in a Mailjet sub-account, which has its own key pair and keeps
+    # its contacts and lists apart from the newsletter on the main account.
+    app.mailjet.travel_mailing_client:
+        class: App\Mailjet\ApiClient
+        arguments:
+            $apiKey: '%env(default::MAILJET_TRAVEL_MAILING_API_KEY)%'
+            $apiSecret: '%env(default::MAILJET_TRAVEL_MAILING_API_SECRET)%'
+            $apiBaseUrl: '%env(default::MAILJET_API_BASE_URL)%'
+            $contactMetadataFields: '%mailjet_contact_metadata_fields%'
+
+    App\Service\TravelMailingListManager:
+        arguments:
+            $mailjet: '@app.mailjet.travel_mailing_client'
+
     App\EventListener\MaintenanceModeListener:
         arguments:
             $options: