What's an email bounce?

When email goes wrong: hard bounces and soft bounces.

Just like regular postal mail, an email will be returned to sender if it cannot be delivered. This is called a bounce.

If you are using Machine Labs you won't see the email coming back as we will automatically deal with it for you.

There are two types of bounces:

1. A Soft Bounce

A soft bounce is a temporary failure to delivery email. This could be because the recipient's email box is full, the receiving email server is too busy or because of some technical failure such as a problem with the internet connection or a failed server.

We automatically re-try soft bounces for you several times before giving up. Soft bounces do not appear as a bounce on your email deliverability reports and do not count towards the 1% bounce limit.

2. A Hard Bounce

A hard bounce means that the attempt to deliver the email has permanently failed. This is usually because the recipient has closed their email account.

A hard bounce will not be retried automatically (and you should not retry either).