A close-up of a smartphone email app showing a full inbox.

Killing Me Softly: Remove Persistent Soft Bounces For a Cleaner Email List

What are soft bounces? How do they differ from hard bounces? And how can you prevent them to ensure your entire audience is receiving your sends?
Article Outline

Email marketers know to watch out for soft bounces and hard bounces in their email campaigns. A single bounced email isn’t usually cause for concern. But when bounces start to add up, it can be signal that deliverability is becoming a problem for your email marketing. What are soft bounces? How do they differ from hard bounces? And how can you prevent them to ensure your entire audience is receiving your sends? Read on to find out.

An email marketer at her desk chews a pencil in frustration while dealing with email soft bounces.
Too many soft bounces can be a problem for email marketers, but we’ll help you before you chew your favorite pencil to splinters.

What is a Soft Bounce?

An email bounces when it isn’t properly received by one of the intended recipients. It’s important to keep an eye out for spikes in hard bounces and soft bounces. Hard bounces are more severe. They happen when your email permanently fails to send because the address isn’t real. Too many hard bounces can damage your IP/Domain reputation, because they’re associated with spammers who are illegitimately guessing at large amounts of email addresses. Soft bounces are less severe than hard bounces. They happen when your email is rejected from the recipient’s mail server for reasons other than an invalid address.

What Causes Soft Bounces?

Soft bounces are a problem. They show that, even though the intended recipient address is real, a transient delivery failure prevented it from being received. A number of things can trigger a soft bounce: spam-related concerns, temporary technical issues, or a full inbox. Spam-related concerns can be resolved with good sending practices, such as list cleansing, quality list sources, and engagement segmentation.

An email inbox on a smartphone appears full, which is likely to trigger a soft bounce.
Full inboxes may not be a temporary problem. They can indicate a soon-to-be-abandoned address.

Soft bounces can also indicate that, while an email address is still active, is isn’t being used. (Think about it: if an inbox stays full, it’s likely because no one is checking it regularly, or at all). If these addresses are abandoned, it’s important to identify the problem sooner than later. Abandoned email addresses spell trouble for email marketers for several reasons:

  • You aren’t reaching the right person with your message
  • The email will probably be shut down eventually, turning into a hard bounce (and potentially damaging your reputation)
  • Spam monitoring sites, like Spamhaus, will pick up these defunct email addresses and use them as spam traps, causing significant disruptions in your sending and damage to your reputation

How Can I Avoid Soft Bounces?

Think of bounces as the dust bunnies of your email marketing list. They are an early indication that your list is old and may need to be cleaned. So, if the Soft Bounce rate is high, first use a list cleanse. For your convenience, Act-On partners with some list cleansing services such as Webbula and Neverbounce. Webbula may be ideal for removing these bounces and providing a deeper cleanse. Second, you can try to automate the process of removing soft bounces. If an email has been abandoned, emailing this contact will continuously cause a soft bounce.

Continuous soft bouncing shows that the contact will not engage and could transform into a threat. Act-On offers a solution to its customers to automate the clean up process for soft bounces: 

  • Click Contacts 
  • Bounces and Opt-Outs
  • Hover over the Soft Bounces list, and click “Move to Inactive Soft Bounces after…”
  • Select how many soft bounces a contact should have in the drop down and the click “Save”

Not an Act-On customer? We won’t hold it against you. (But you should give us a try!)

How Many Soft Bounces Should I Allow?

How many soft bounces to allow depends on how often you typically email a contact and the risk level you are willing to take. Here are some guidelines based on your email sending frequency:

  • Daily sends – 10-20
  • Two sends per week – 4-7
  • One send per week – 3
  • One send per month – 2-3

These thresholds allow a buffer for temporary issues (e.g. blocklisting) while still removing repeat bounces in a timely manner.

This has been a guest post from Matthew Volkman on our Deliverability Team.

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