diff --git a/config/packages/dev/mailer.yaml b/config/packages/dev/mailer.yaml
deleted file mode 100644
index 59f449a903..0000000000
--- a/config/packages/dev/mailer.yaml
+++ /dev/null
@@ -1,3 +0,0 @@
-framework:
-    mailer:
-        dsn: 'null://null'
diff --git a/config/packages/mailer.yaml b/config/packages/mailer.yaml
index 56a650d89b..6155a6d6bd 100644
--- a/config/packages/mailer.yaml
+++ b/config/packages/mailer.yaml
@@ -1,3 +1,8 @@
 framework:
     mailer:
         dsn: '%env(MAILER_DSN)%'
+
+when@dev:
+    framework:
+        mailer:
+            dsn: 'null://null'