Managing Bounces, Unsubscribes, and Complaints

Complaints, bounces, and unsubscribes to your newsletters are an indicator of its overall effectiveness and quality. They represent not only how happy your subscribers are with receiving your emails, but also how they feel about your entire email marketing strategy. Each of these factors affects your list in different ways. Learn how to manage the quality of your mailings and contact lists.

• The Importance of Quality Control in Your Newsletters
• Types of Bounces
• Different Reasons for Bounces
• Email Address Statuses
• Tracking and Re-subscribing Unsubscribed Contacts
• Understanding the Rates That Influence the Quality of Your Mailings

The Importance of Quality Control in Your Newsletters

A person unsubscribes from a list when they no longer find the emails sent to them relevant, and if they continue to receive emails after unsubscribing, they might potentially report them as SPAM. For this reason, understanding the following terms is essential to monitor and maintain the health of a list. Additionally, some email addresses may also cause bounces depending on their nature or whether they are active or not. It is also important to avoid bounces, as a high bounce rate can negatively impact your email deliverability, which could ultimately hurt your engagement rates.

To find a solution to undelivered emails, check out our undelivered email troubleshooting article.

Types of Bounces

A "hard bounce"

This occurs when an address no longer exists (or perhaps never existed). These situations can negatively affect your account, sometimes resulting in suspension. All hard bounces will therefore be removed from the list. If the address never existed, you can avoid this by simply sending a subscription confirmation email.

A "soft bounce"

Due to a "temporary" issue, the email is currently unavailable. An email address will automatically be removed from the list after four soft bounces. It is important to note that your reports provide very detailed information about your email bounces, including several types of bounces not mentioned here.

These emails are thus removed to avoid SPAM complaints. Furthermore, this helps improve statistics for future emails.

Different Reasons for Bounces

Full inbox

A full inbox prevents the mail server from delivering the message to the recipient.

Address change

An address change response indicates that the recipient has changed their address and informs senders of this update.

Automated reply

The recipient’s email client usually sends an automated reply (often in the form of an out-of-office notice). This indicates that the recipient is temporarily unavailable, unlike bounces. These notifications are useful when sending time-sensitive information, as they alert you that the recipient may not see it immediately. Otherwise, they can be safely ignored.

Transient bounce

Often, the sender's mail server generates a transient bounce, informing the sender that the message was not delivered, but the server is trying again. This continues until two days have passed since the message was sent. However, there is usually no need to worry about transient bounces. You might also receive the following message: "Warning: message still undelivered after 4 hours."

Challenge/Response test

A "Challenge/Response" reply is a message sent by special filtering software that only accepts messages from known senders. This type of filter automatically sends a response with a challenge (a required question or action) to the sender of the email. The message will not be delivered if the challenge is not correctly completed.

Blocked email

This indicates that the recipient's mail server is blocking your email. You might see the following messages:

• 550 Message REFUSED by peer
• 552 Blocked by filters

DNS failure

This indicates that a DNS issue has temporarily prevented the delivery of the email to an address.

Hard bounce

A hard bounce is an email message returned to the sender due to an invalid recipient address. The domain name might not exist, or the recipient may be unknown, resulting in a hard bounce.

Email address statuses

• Hard bounce
• Soft bounce
• SPAM - If the status displays "FBL", then it is a SPAM complaint. Obtain written proof that the contact wants to resubscribe and send it to our support team.
• Unsubscribed - If the contact is unsubscribed, obtain written proof that they want to resubscribe, then send it to our customer support.
• Pending - The account has not been confirmed through the double opt-in process: the confirmation email has been sent to the recipient (asking them to click on the link), but the recipient has not clicked the link. Therefore, the account is not yet considered active, and no emails can be sent to it.
• Active - The account is active and should be able to receive your newsletter campaigns.

Tracking and Re-subscribing Unsubscribed Contacts

You can easily track your unsubscribed contacts to understand the reasons or to re-subscribe a contact unsubscribed by mistake. To improve your community's experience with your newsletters, check out our article Allowing my contacts to subscribe to my newsletters based on their interests.

Viewing the list of unsubscribed contacts

1. Go to your account in the newsletter section, then click on the Contacts tab.
2. In the left-hand menu under filter options, select "Status," then add "is" and "Unsubscribed" in the lists below. You will get a filtered list of contacts who have unsubscribed or whom you have manually unsubscribed. 

3. Click on one of the contacts. You will be redirected to their detailed profile. 
4. By clicking on the Activity tab at the top of the profile, you can see the contact's activity, such as the moment they subscribed to your newsletters or when they unsubscribed.

Re-subscribing a contact

Someone may ask you to re-subscribe them to your newsletters. If that happens, you will need to manually add their contact information.

1. Click on the + icon in the top right corner, then select Add a contact.
2. Choose a list, enter the email of the unsubscribed person, and fill in other fields if necessary.
3. Check the box I confirm that I have permission, then click on Save contact.
4. By searching for their email in your list of active contacts, you will see that they are now subscribed.

Understanding the rates that influence your email quality

Bounce rate

The bounce rate is calculated as follows:

[Total bounces / Total recipients]

There should be no more than 1% hard bounces. Additionally, your bounce rate can be influenced by the following factors:

• Industry type
• Is your list up-to-date?
• What is the frequency of your mailings? The rate for each campaign decreases as you send more frequently.

Unsubscribes

The unsubscribe rate is calculated as a percentage of:

[Total unsubscribes / Total recipients]

Always remember that unsubscribing is preferable to being reported as SPAM. Unsubscribe links are usually included in email templates. To add an unsubscribe link to your email, check out our guide on how to do this.

Complaints

The SPAM complaint rate is calculated as follows:

[Total complaints / Total emails sent to specific internet service providers (ISPs)]

As soon as someone marks your emails as SPAM, they are permanently removed from the list.

Expected results:

[0% – 0.1%]

Follow best practices to avoid complaints and send a test email to yourself (check where it lands) before launching your campaign. It should never exceed 0.25% (1 email out of 400 sent).

Keep in mind that ISPs (internet service providers) also monitor these numbers. If you consistently have moderate to critical levels of bounces/SPAM, it is only a matter of time before your emails end up in a recipient's spam folder or get permanently blocked.