diff --git a/prisma/migrations/20250312223725_check_reply_cost_positive/migration.sql b/prisma/migrations/20250312223725_check_reply_cost_positive/migration.sql
new file mode 100644
index 00000000..7736c04b
--- /dev/null
+++ b/prisma/migrations/20250312223725_check_reply_cost_positive/migration.sql
@@ -0,0 +1,2 @@
+-- Add constraint to ensure replyCost is positive
+ALTER TABLE "Sub" ADD CONSTRAINT "Sub_replyCost_positive" CHECK ("replyCost" > 0);
\ No newline at end of file