diff --git a/.env.dist b/.env.dist
index 0c279b85..bd33bdae 100644
--- a/.env.dist
+++ b/.env.dist
@@ -231,6 +231,8 @@ POSTGREY_DELAY=300
 POSTGREY_MAX_AGE=35
 # response when a mail is greylisted
 POSTGREY_TEXT=Delayed by postgrey
+# whitelist host after N successful deliveries (N=0 to disable whitelisting)
+POSTGREY_AUTO_WHITELIST_CLIENTS=5
 
 # -----------------------------------------------------------------------------------------------------------------------------
 # ---------------- SASL section -----------------------------------------------------------------------------------------------