email bounce back

How to Prevent Email Bounce Back Effectively?

You send a carefully crafted email to find it back in your inbox as “failed to deliver”.

This leaves you exasperated since it is an important marketing email, and you have put in a lot of effort in creating it.

This is called email bounce back, and it is one thing a marketing team wishes to avoid, as email deliverability decides how successful your campaign is.

Email bounce rate is an indicator of the number of emails undelivered. It is calculated as the number of bounces divided by the total number of emails sent. The lower the rate, the better.

There are three types of email bounce back possible:

  • General bounce: Here, the firewall settings of the receiver may prevent an email from reaching the inbox. This is not due to the sender’s fault and does not affect his reputation score.
  • Hard bounce: When the recipient’s email ID is expired or invalid, or you have entered the wrong address due to a typo, it results in a hard bounce. This becomes a permanent failure, and the email is not sent.
  • Soft bounce: This is due to temporary issues, which may be due to an overflowing inbox of the receiver, the recipient setting an out-of-office response, a large email, the server not functioning, etc. Once the issue is corrected—for example, the recipient clears the inbox—the mail is delivered.

Before moving on, we should first understand the common reasons for a bounce.

  • The email address is not valid: When you send a message to an invalid email address, it is not delivered and comes back to you. This happens when the email service provider cannot find the mail address either because it does not exist or has expired. A small spelling error may also lead to a valid email becoming invalid.
  • Your IP address is blocked: Your emails will not be delivered whenever your IP address is blocked to avoid spam. This happens when you share the IP address with those who are sending spam emails.
  • Overload of server: When the recipient’s server is overloaded, it does not accept any further emails. This may be a temporary failure and can be termed a soft bounce.
  • Reputation score of the sender: The sender’s reputation score is an important aspect. The lower your score, the more the chances for email bounce.
  • Inbox full: Your emails bounce back when the receiver’s inbox is full due to exceeding storage limits. But this is also temporary and is a case of soft bounce and will be through when the inbox is cleared.
  • Spam identification by server: When the content of the email appears to be spam, it is taken to the spam folder, or it may bounce back. The server checks the incoming email with a spam filter and can send it back without even notifying the receiver. 
  • Email size: The size of the email sent may also be a reason for the bounce. the attachments sent in the email may exceed the allotted limit and not be delivered.

Why is email bounces a cause of concern?

Email bouncebacks affect your email deliverability, meaning your marketing strategy can take a dive.

It becomes a serious concern when the hard bounce percentage is more or less 5% regularly.

IP reputation can be severely affected when you continue to send emails to hard bounce addresses.

The main motto of sending an email is lost here, which could affect your business.

When a hard bounce comes to your notice, you should check for reasons to rectify the same.

The following are some of the ways you can effectively avoid bounceback.

Establish authenticity of emails: This can be done through the double opt-in method. Whenever users register themselves, you can ask them to verify their email Id. This can give you the assurance that the email addresses are correct. Since the confirmation is given by the users, it results in doubly ensuring its authenticity.

Now when the same is practiced for all addresses on your email list, you have only verified emails. The emails sent to these IDs will not bounce back.

Beware of your content: Anything from the subject line, message content, etc., can raise the alarm for spam. When your content is termed spam, it will lead to an increase in bounce rate.

Even though your emails are for marketing, avoid words like free, offer, etc, that can move your content to the recipient’s spam folder. Your email marketing potential will be lost here.

Also, have a judicious mix of text and HTML in your email message, avoid providing many links, and ensure that not much of the text is in bold or caps.

Email list hygiene: The list of contacts you maintain should be updated from time to time to eliminate expired email addresses. When an email address is not used by a person for a long, it will be declared expired by the email provider. Remove such mail addresses and have an active subscriber list. This can help reduce bounce notifications.

Check the spellings: If you do not want to receive a bounce message, you have to check for any typo errors in the email addresses. When you send an email campaign, it is imperative that your email list is authentic. A full stop after the .com or a typo in the ID may prevent the email from being sent. After so much effort to send a campaign across, typos should not create a hurdle.

Do not purchase emails: When you purchase email lists, they may contain addresses of those who are not your subscribers. The moment they receive your email, they consider it spam and will mark it as spam without even opening it. This will give rise to a high email bounce rate and impact your reputation negatively. Your mailbox providers will have a wrong notion about the emails sent through your IP address, and the chances that your future campaigns will take a dip is present.

Check the domain: It is always better to avoid free domains and create business domains to have a very specific reach. You may not be able to authenticate emails in the free domain. This will result in email bounce as they are treated as spam. When sending from a business domain, you have authenticity, and the recipient knows where the email is from.

Restrict your daily limit: You should schedule the number of emails you send per day. The email service provider fixes the number of emails you can send in a day, the excess of which bounces back. If you watch over, you can avoid bouncebacks. If this continues on a regular basis, your account may also be blocked in the future.

Check your reputation score: Emails may also bounce when the sender’s reputation score is low. This is the value the domain gets based on the email activity that it maintains. You should maintain a good score, so your emails do not reach the spam folder or get back to you. The scores can be checked online, and you get several free tools for the same.

Eliminate inactive recipients: In a phased manner, you can remove those recipients who do not give response to your emails. The waiting period can be around three months to watch if there is any response. If the receivers are inactive, it means they are not engaging with your brand. Periodic inactivity will lead to the emails being directed to the spam folder automatically.

Remove the hard bounces: When you identify a hard-bounce email, remove the address at once from your list of email addresses. In many cases, the email delivery agency removes the hard bounce on its own. When it is a soft bounce, however, it may try to resend it as the issue is only temporary. If you repeatedly send to hard bounce addresses, it affects your bounce rate.

Maintain consistency in mailing: Always be consistent in mailing your subscribers. Being in touch with them regularly will let you know if there is any change in email address. You can keep track of the same and update them to avoid bouncing emails.

Try to avoid sending random emails: Do not keep your email volume erratic. The email server and the service provider detect the flow of emails, and when they find an unusual increase in the flow compared to your regular mailing pattern, it raises a red flag. Your IP address may be under suspicion, and your bounceback rate may increase if you continue to do so. 

The gap between successive emails: There should be some time gap between the two successive emails sent. This can help to reduce the chance of bouncing back. It leads to spam detection since it looks like a bulk promotional email. Online email services help you with maintaining the ideal time gap.

Track your bounce rates: Your target should be to stay within the acceptable bounce rates. An acceptable email bounce rate is considered to be less than 5%. Track your performance regularly, and do not let your rates increase. This may lead to the suspension of your account. 

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From the above, it is clear that you should follow certain practices to avoid bouncing emails and have a successful email marketing strategy.

Email marketing is a powerful tool for email marketers; therefore, it is crucial that you stay within the acceptable bounce rates.

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