What causes bounced emails? 3 easy tips to lower your bounce rate


Email is a critical component of any company’s digital marketing efforts.

First of all, about 102.6 trillion emails get sent every year, and the average email user receives 13 commercial emails per day.

But before you assume that email marketing is just a lot of noise to get lost in, consider this: Email marketing has a 4,400 percent ROI (return on investment), meaning that every dollar you spend has the potential to result in a $44 return.

Check out 48 more statistics that show the value of email marketing.

However, if your emails are bouncing, how effective can you really be?

Let’s dive into what causes bounced emails and three tips to avoid them from affecting your email marketing.

What causes bounced emails?

When a recipient’s email server notifies you that your email was not delivered, that’s a bounced email.

Bounced emails both lower your potential conversion rates (i.e. sales) and negatively impact your IP reputation, which can cause your emails to get blocked, flagged and/or blacklisted.

There are two types of bounced emails: soft versus hard.

A soft bounce is a temporary issue that is preventing your email from delivering. This can range from the recipient’s email inbox being full to the recipient’s server not being able to process the delivery, for example. You’ll see a soft bounce notification code that starts with a “4xx.” 

While these temporary issues typically resolve themselves, keep in mind that five consecutive soft bounces can turn into a hard bounce. And a hard bounce can definitely impact your IP reputation (while a soft bounce has less of an impact).

Speaking of a hard bounce, this is when the delivery issue is permanent, such as an invalid email address. You’ll see a hard bounce notification code that starts with a “5xx.”

Depending on the type of bounce, the cause can be a range of issues, including (but not limited to):

  • Invalid email addresses
  • Sender IP reputation
  • Mailbox is full
  • Mailbox is inactive
  • Email message is too large
  • The domain name does not exist
  • Blocked due to content
  • Recipient’s email server down or offline
  • Mailbox not configured correctly
  • Recipient’s email server sent too many messages during a period of time
  • Aggressive spam filters

How to avoid bounced emails

No matter how many reasons are out there for bounced emails, the key is to avoid them as much as possible.

Only use clean data

Data degradation is a huge issue for many businesses, no matter how they contact their customers and leads. Phone numbers, email addresses and mailing addresses all can easily change over time.

Be sure to scrub your email lists and remove any incorrect or old emails that can impact your bounce rate and IP reputation. This can be a fairly simple process to perform regularly depending on the email marketing tool you’re using.

Also, avoid buying any lead lists. This is an archaic method at this point that can lead to very unreliable data.

Use segmentation, personalization

Sending broad email messages to a broad audience risks your emails manually getting marked as spam by your recipients (if they don’t feel like the messaging is intended for them specifically).

You can help prevent this by segmenting (breaking up) your contact database into groups that are relevant to your marketing. Examples include (but are not limited to):

  • New customers
  • Customers who have spent over a certain amount with you
  • Age demographics
  • Geographic demographics
  • Customers who haven’t purchased from you in a particular time period
  • Leads who have never purchased from you

As far as personalized content, this ranges from delivering a message that is right for a specific audience (addressing their specific problems and pain points) to including their first name in the subject line of the email.

Both of these functions make your content more relevant and engaging to the recipient, which not only reduces your bounce rate but can also lead to more conversions and sales. Just remember: The more unique the message, the better.

Fortunately, DailyStory offers powerful tools that help you accomplish both detailed segmentation and automated personalization.

Avoid triggering spam filters

No email marketers want to end up in spam (or bounced entirely because of an aggressive spam filter), but it can be easy to do if you’re not keeping an eye on the words, phrases and even grammar in your email.

Examples of what you should be doing include (but are not limited to):

  • Use standard formats and fonts (including capital letters and crazy colors)
  • Do not use excessive links (anything more than six links within the text can get flagged)
  • Compress your images and watch your image-to-text ratio (70 percent text and 30 percent images is a minimum to dodge spam filters)
  • Watch your use of exclamation points (too many is a trigger)
  • Avoid the most common spam words and phrases (such as these)

For more, check out our nine tips to maximize your inbox placement and get your emails seen.

In conclusion

Your bounce rate is critical in your success with email marketing. Ideally, you’ll want to maintain a bounce rate below 1.19 percent. 

However, a generally accepted bounce rate is between 2 percent and 5 percent. If your rate is more than 5 percent, we recommend starting with a data scrub and then optimizing your content (and creating targeted segments) along the way.

To dig deeper, you can view our complete Bounced Email Guide, including a breakdown of the common bounce codes you’ll likely see reported.

Need assistance with your digital marketing? Curious about just how much of your efforts can be automated (and more effective)? Schedule your free demo with us today.

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