What’s a Soft Bounce vs. Hard Bounce in Email?

Your email campaigns need to hit the inbox to drive the subscriber engagement and email marketing performance you want. If your email has bounced, it’s worth digging into to understand what stood in the way of your email being delivered–and what you can do about it.

Read on to learn more about the difference between a soft bounce vs hard bounce email, where to find bounce information for your email marketing campaigns–and what to do with it.

What is a soft bounce?

A soft bounce is a temporary bounce. Though the delivery of your current message was unsuccessful, you may be able to deliver another email to that address at a later date. A soft bounce could be due to issues like:

• Too many people have marked your emails as spam.
• You’ve been put on a blocklist
• The recipient’s mailbox is full
• The email account has been temporarily suspended
• Unforeseen errors or outages at the receiving mail server

How to deal with a soft bounce

Soft bounces may not need immediate attention because they usually resolve on their own–but they should be closely monitored.

• Remove the email from your list after three bounces
• Understand the interval in which those bounces happened. For example, was it over the course of a day or a week?
• Ask your ESP what they do about soft bounces. Do they automatically attempt to resend your message? When and how many times until they give up? At what point do they convert a soft bounce to an undeliverable email address on your suppression list?

What is a hard bounce?

A hard bounce is a permanent bounce, meaning an email will not be received by that email address. It may be the result of an unknown user error, which is caused when an email address:

• Is invalid because it doesn’t exist or contains a typo (e.g., @gmial.com instead of @gmail.com)
• Has been deactivated, such as when someone leaves a company or abandons a free email account
• Has blocked your emails from being delivered

How to deal with a hard bounce

Actively managing hard bounces is a critical step when cleaning up your email list.

• Confirm your specific ESP’s practices for hard bounces. Most email service providers (ESPs) take care of this for you, but ensure how they handle this process. Do they automatically correct common email address typos? After how many hard bounces will your ESP mark an email address undeliverable–and for which kinds of hard bounce?
• Follow best practices for manual removal. We recommend deactivating the hard bounce emails or adding them to a suppression list as part of your list hygiene practices. This removes the possibility that you’ll accidentally send to email addresses you know will hard bounce.

Know where to find bounce information in your ESP

Finding soft bounce vs hard bounce email information varies by ESP, but you can generally find bounce rate metrics in each individual mailing’s report, along with the rest of your delivery data. For example, here’s what you might see:

From there, you can dig into either your soft bounces vs hard bounces to see a full list of each recipient and their bounce code—which is the data you’ll need to start managing your list.

Actively manage your email lists

When either a hard or a soft bounce occurs, it means it’s time to roll up your sleeves and dig into your lists. Repeatedly sending email to addresses that hard bounce can indicate to internet service providers (ISPs) that you have bad list hygiene practices.

We recommend reviewing your bounce stats at least on a weekly basis. Depending on the size and scope of your email marketing program, you may want to check more often, or more often during peak seasons.

Data quality is an important metric for ISPs when they’re deciding whether your emails are spam or not and can contribute to your sender reputation.

Actively managing your list isn’t just good for email deliverability, it’s good for engagement, too. When you send to a cleaner list, you’re more likely to be sending to people who want to receive and will engage with your email. That’s a win-win.

Originally published on October 20, 2016, by Kayla Voigt. Last updated October 19, 2022