Bounce Responses

You’ve sent an email blast to 1,000 people on your list, but your report shows 25 of them bounced. Should you be happy or upset? It can be difficult to know.

There are a variety of types of bounces, and you can take action to fix them and keep your list clean. It’s important to understand what’s going on and what an acceptable bounce rate is.

What Are Bounce Responses?

A bounce happens when an email is not deliverable. This shows up in your reporting so that you can identify email addresses that are not working correctly.

Hard bounces mean that the email address doesn’t exist on the target server or that the user was not found. There are a variety of bounce responses this can generate, and the exact bounce response will tell you what the problem is.

Soft bounces happen when the email address exists but there’s a problem with the server. Maybe the email box is full or the user only allows previously authorized senders into the inbox. The mail server could also be down.

Knowing the bounce response is key to figuring out what’s wrong with the email address and whether you should remove it from your list.

What Does Each Bounce Response Mean?

Generally a bounce response tells you what went wrong with the delivery. Sometimes the response is “General bounce”, which is a type of soft bounce that doesn’t have a specific reason for delivery failure.

Some hard bounce responses include:

• Unknown alias
• Address rejected
• No such user
• Bad destination mailbox

If you are getting these bounce responses, there’s no point in keeping the address on the list. There’s no one on the other end.

Some soft bounce responses are:

• Challenge response (anti-spam measure)
• DNS failure (server isn’t available)
• Mailbox full
• Mail block (often includes a reason, like known spammer)

Take a look at the reason for the bounce and see if you can take action to improve deliverability. A full mailbox generally means the user abandoned the address. A DNS error might be temporary and you can try resending again later.

How Can I Reduce Email Bounces?

The key to reducing email bounces is to keep your email list clean and up-to-date. Avoid buying mailing lists and use organic opt-in campaigns instead.

Using verified emails can help you avoid having bots and fake email sign-ups. Pruning your list regularly to avoid inactive accounts will also help.

If you get bounces, review the reasons and make a decision about keeping the addresses on your list. As long as your bounce rate is under 3%, you’re in good shape!