diff --git a/data/production-email.template b/data/production-email.template
index 84d7d5989..b3d3dc4a0 100644
--- a/data/production-email.template
+++ b/data/production-email.template
@@ -17,8 +17,8 @@ this certificate with a newer one that covers more or fewer names than
 the list above, you may be able to ignore this message.
 
 If you want to stop receiving all email from this address, click
-|UNSUB:https://mandrillapp.com/unsub| (Warning: this is a one-click action
-that cannot be undone)
+*|UNSUB:https://mandrillapp.com/unsub|*
+(Warning: this is a one-click action that cannot be undone)
 
 Regards,
 The Let's Encrypt Team
diff --git a/data/staging-email.template b/data/staging-email.template
index b837d2c30..f4fdf9be5 100644
--- a/data/staging-email.template
+++ b/data/staging-email.template
@@ -20,8 +20,8 @@ For details about when we send these emails, please visit
 https://letsencrypt.org/docs/expiration-emails/.
 
 If you want to stop receiving all email from this address, click
-|UNSUB:https://mandrillapp.com/unsub| (Warning: this is a one-click action
-that cannot be undone)
+*|UNSUB:https://mandrillapp.com/unsub|*
+(Warning: this is a one-click action that cannot be undone)
 
 Regards,
 The Let's Encrypt Team