diff --git a/.well-known/mta-sts.txt b/.well-known/mta-sts.txt
new file mode 100644
index 0000000..a861061
--- /dev/null
+++ b/.well-known/mta-sts.txt
@@ -0,0 +1,4 @@
+version: STSv1
+mode: enforce
+mx: mail.tommytran.io
+max_age: 604800
\ No newline at end of file