What’s the difference between a hard and soft bounce ?

email-soft-bounceWhen it comes to keeping your lists clean and knowing which emails are good or not, a hard or soft bounce are the only real way to know which is which. Many white listed servers are very strict about not having a list with a “bounce” rate of more than 1% and they really mean Hard bounces or dead emails, not soft-bounced emails.

If you have your own server for example and use IEM or Interspire as your mailing software, you get all this lovely data right on your site which works the exact same way as any white listed server as Mail-chimp or Constant Contact.

After you mail out to a list, you will get back 1 of 2 bounces a Soft Bounce or Hard bounce, any hard bounce will be noted and that email address will/should never be mailed to again from any white listed server or IEM as it keeps track of that invalid email and makes sure you never try to contact them again.

Below are the basic explanations of a bounce:

Hard bounce

A hard bounce is an email message that has been returned to the sender and is permanently undeliverable. Causes include invalid addresses (domain name doesn’t exist, typos, changed address, Invalid email, dead email etc.) or the email recipient’s mail server has blocked your server.

Soft bounce

A soft bounce is an email message that gets as far as the recipient’s mail server (it recognizes the address) but is bounced back undelivered before it gets to the intended recipient. A soft bounce might occur because the recipient’s mailbox is full “user over quota”, the server is down or swamped with messages “server temporarily unavailable” , or the message is too large.