How to Reduce Email Bounce Rate and Improve Deliverability

 How to Reduce Email Bounce Rate and Improve Deliverability

Understanding and monitoring your email bounce rate is essential for maintaining a successful email marketing campaign. By analyzing the reasons for bounces and taking action to reduce them, you can improve your overall email deliverability and increase your chances of reaching your target audience effectively. 

What is the Email Bounce Rate?

Email bounce rate refers to the percentage of emails that were not successfully delivered to recipients’ mailboxes. Bounces can occur for various reasons, such as invalid email addresses, full mailboxes, server issues, or spam filtering.  Monitoring email bounce rates is crucial for any email campaign, as high bounce rates can damage sender’s reputation and affect deliverability rates. Additionally, bounced emails do not reach the intended recipients, resulting in wasted time and resources.

There are two types of email bounces :

1. Hard bounce : hard bounce is a permanent as you can experience a hard bounce when an email cannot be delivered due to a permanent issue, such as a non-existent email address or domain, or a blocked email server. These emails should be removed from the email list immediately to prevent future bounces.

2. Soft bounce : A soft bounce rate occurs when an email cannot be delivered temporarily, such as due to a full mailbox, server issues, or a content filter. Soft bounces may resolve themselves over time, but repeated soft bounces should also be addressed to prevent sender reputation damage.

How Email Bounce Rate Is Calculated? 

The bounce rate is the percentage indeed expressed as a percentage. Email bounce rate is typically calculated as the percentage of emails that were not delivered successfully out of the total number of emails sent. It’s an important metric to gauge the health of your email list and the effectiveness of your email campaigns.

Here’s the equation :

Bounce Rate = Number of bounced emails / Total number of emails sent 100%

Let’s say you sent out 1000 emails and received back 50 bounce notifications. To calculate the bounce rate :

Bounce Rate = 50 / 1000 x 100% = 5%

So, in this example, the bounce rate is 5%.

Monitoring your bounce rate regularly can help you identify issues such as invalid email addresses, full inboxes, or other delivery problems, allowing you to take corrective actions to improve your email deliverability and campaign effectiveness. The average bounce rate across industries can vary depending on factors such as industry, audience, list quality, and email sending practices. However, as a general guideline, a bounce rate below 2% is typically considered acceptable for most email marketing campaigns.

Why Email Bounce is so Important?

Email Bounce is an essential metric for several reasons :

  1. A high email bounce rate can indicate issues with the quality of your email list. It might contain outdated or invalid email addresses, leading to failed deliveries.
  2. Maintains Sender Reputation : Email service providers (ESPs) monitor bounce rates closely. Consistently high bounce rates can negatively impact your sender reputation. A poor reputation can result in emails being flagged as spam or not being delivered at all, affecting your overall email deliverability.
  3. Improves Campaign Effectiveness : High bounce rates mean your emails are not reaching their intended recipients. By addressing bounce issues, you can ensure that your messages are reaching the right audience, increasing the effectiveness of your email marketing campaigns.
  4. Cost Efficiency : Many email marketing services charge based on the number of emails sent. If a significant portion of your emails bounce, you’re essentially paying for emails that never reach their destination. Reducing bounce rates can help optimize your email marketing budget.
  5. Legal Compliance : High bounce rates can also raise concerns regarding compliance with anti-spam regulations like the CAN-SPAM Act in the United States and GDPR in the European Union. These regulations require marketers to maintain clean email lists and ensure that recipients have explicitly opted in to receive communications.

How to reduce email bounce rate

Reducing email bounce rates is essential for maintaining a healthy email marketing campaign. Take steps to reduce your bounce rate here are several strategies you can implement to reduce your email bounce rate:

1. Verify Email Addresses

Before sending out your campaign, use email verification tools to ensure the email addresses on your list are valid. These services can help identify and eliminate invalid, disposable, or risky email addresses that are likely to bounce.

2. Keep an Updated Email List

Reducing the email bounce rate involves maintaining a clean and validated email list. Regularly keep your email list clean by removing addresses that consistently bounce. Ensuring a clean and accurate email list begins with collecting valid email addresses. If recipients are not engaging with your emails (no opens/clicks over an extensive period), consider removing them or trying a re-engagement strategy. Start cleaning your email list by removing inactive users and those who haven’t opened your emails in a while. Can also run campaigns to disengage contacts, asking if they want to continue receiving your emails. Email warming also allows senders to observe and establish engagement patterns with their email recipients. By gradually increasing the volume of emails sent and monitoring engagement metrics such as open and click-through rates, bounce rates, senders can identify trends and adjust their email content, frequency, and targeting to optimize engagement and reduce bounce rates.

Maybe they are not even bothered to unsubscribe, but you can do it for them if they don’t confirm again.

3. Segment Your Audience

Segmenting your email list ensures you send relevant content to each subgroup. This relevance can reduce the chance of soft bounces caused by low engagement and spam complaints, which can temporarily affect your sender reputation.

4. Use a Double Opt-In Process

This process involves sending a confirmation email to new subscribers, asking them to verify their email address. This extra step helps ensure you are only adding valid and interested email addresses to your list. It is better to use automation to streamline contact list management for double opt-ins.

5. Maintain a Good Sender Reputation

Internet Service Providers (ISPs) track your sending habits. If you send emails to invalid addresses frequently, it may harm your sender reputation, leading to an increased bounce rate. Maintain healthy sending practices by adhering to email marketing laws, avoiding spammy content, and not exceeding volume thresholds. Increase your email bounce rate occurs when emails are sent to invalid or inactive addresses, leading to delivery failures and potentially impacting sender reputation.

6. Optimize Your Email Content

Check your email and keep track of it that your emails are not being rejected because they look like spam. Use a clear and concise subject line, avoid overly salesy language, and ensure your HTML emails are well-coded. Also, include a plain text version for better compatibility. Because of this, you should perform A/B testing to determine which subject lines, email copy, CTA buttons, etc. are most impactful with your subscribers. This will allow you to see which one of the two performs the best and whether it can bring your bounce rate down.

7. Authenticate Your Emails

Use SPF (Sender Policy Framework), DKIM (Domain Keys Identified Mail), and DMARC (Domain-based Message Authentication, Reporting, and Conformance) records for email authentication. This helps ISPs verify that your emails are legitimately from you, reducing the chance of them being bounced or sent to spam.

8. Avoid Sudden Changes in Email Volume

ISPs might view a sudden spike in sent emails as suspicious, potentially affecting your deliverability. Gradually increase your email volume, especially if you have a large list or are starting a new campaign. Email warming involves gradually increasing the volume of emails sent from a new IP address or domain over a period of time. By starting with a low volume of emails and gradually ramping up, ISPs and email providers are less likely to flag the sender as suspicious or spammy, which can help maintain a positive sender reputation and reduce bounce rates.

9. Monitor Feedback Loops

Many ISPs offer feedback loops that notify senders when recipients mark their emails as spam. Subscribe to these feedback services to identify and address issues promptly, adjusting your strategy to reduce complaints and ultimately, bounce rates.

10.  Provide Clear Unsubscribe Options

Make it easy for subscribers to unsubscribe from your emails. A clear and prominent unsubscribe link reduces the likelihood of recipients marking your emails as spam, which can negatively impact your sender reputation.

By combining these tactics with a robust email marketing strategy, businesses can optimize the deliverability, engagement, and overall success of your email campaigns. Above are several ways to reduce your email bounce rate.

How Email Address Verification is Done?

Email verification is typically done through a process that involves checking the validity and deliverability of an email address. Here’s an overview of how email verification is typically performed:

  1. Syntax Check : The first step is to verify that the email address has a valid syntax according to standard email formatting rules. This involves checking for common mistakes such as missing “@” symbol, invalid characters, or extra spaces.
  2. Domain Check : Once the syntax is validated, the domain of the email address is verified to ensure it exists and is properly configured to receive emails. This involves checking the DNS (Domain Name System) records associated with the domain.
  3. MX Record Lookup : The Mail Exchange (MX) records of the domain are queried to determine the mail servers responsible for receiving emails for that domain. This step confirms that the domain is configured to accept emails.
  4. SMTP Handshake : A connection is made to the recipient’s mail server using the Simple Mail Transfer Protocol (SMTP). During this handshake process, the sending server communicates with the recipient server to verify if the email address exists and is deliverable.
  5. Address Verification : The recipient server may perform additional checks to verify the existence of the specific email address within the domain. This may involve querying the server’s user database or performing other validation checks.
  6. Response Analysis : Based on the responses received during the SMTP handshake and address verification process, the email verification service determines the validity and deliverability of the email address. If the address is deemed valid and deliverable, it is considered verified.
  7. Flagging Risky Addresses : Some email verification services also assess the risk associated with an email address, flagging addresses that may be associated with spam traps, temporary email services, or other suspicious activity.

Overall, email verification helps ensure that email addresses collected for marketing, communication, or other purposes are valid, deliverable, and less likely to result in bounces or deliverability issues.

How to Set up SPF, DKIM, and DMARC for a Domain 

Setting up SPF, DKIM, and DMARC for a domain involves making changes to the DNS (Domain Name System) records associated with that domain. Here’s a step-by-step guide on how to set up each of these authentication mechanisms :

1. SPF (Sender Policy Framework) :

  • Log in to your domain registrar or DNS hosting provider’s website.
  • Access the DNS management section for your domain.
  • Create a new TXT record for your domain.
  • In the TXT record, specify your SPF policy.

For example :

v=spf1 include : ~all

Replace ‘’ with the domain name or IP address of your mail servers. You can also include multiple servers or services as needed.

  • Save the changes to publish the SPF record.

2. DKIM (Domain Keys Identified Mail) :

  • Generate a DKIM key pair using your email server software or a third-party service.
  • Log in to your domain registrar or DNS hosting provider’s website.
  • Access the DNS management section for your domain.
  • Create a new TXT record for your domain.
  • In the TXT record, add the DKIM public key generated earlier.

The record typically looks like this : IN TXT “v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC…”

Replace ‘selector’ with the DKIM selector, ‘’ with your domain, and ‘p=’ with your DKIM public key.

3. DMARC (Domain-based Message Authentication, Reporting, and Conformance)

  • Create a DMARC policy for your domain. This policy specifies what action to take when an email fails SPF or DKIM authentication.
  • Log in to your domain registrar or DNS hosting provider’s website.
  • Access the DNS management section for your domain.
  • Create a new TXT record for ‘’. Replace ‘’ with your actual domain.
  • In the TXT record, specify your DMARC policy.

For example : 

v=DMARC1; p=quarantine; rua=mailto:[email protected]; ruf=mailto:[email protected]; fo=1; adkim=s; aspf=s;

Adjust the policy (‘p=’) and reporting addresses (‘rua=’ and ‘ruf=’) as needed. Common policy options include ‘none’, ‘quarantine’, or ‘reject’.

  • Save the changes to publish the DMARC record.

After making these changes, it may take some time for the DNS changes to propagate across the internet. Once propagated, SPF, DKIM, and DMARC authentication will help improve the security and deliverability of your domain’s email communications. Reasons why email bounces signify delivery failures, offering concise insights into address validity and deliverability challenges.


In conclusion, understanding and actively managing ways to reduce email bounce rates is crucial for maintaining a successful email marketing campaign. By analyzing the reasons for bounces and implementing strategies to reduce them, you can improve overall email deliverability and increase your chances of reaching your target audience effectively. Monitoring bounce rates, distinguishing between hard and soft email bounce, and taking appropriate actions are essential steps in maintaining a healthy email list and optimizing campaign performance. Additionally, implementing authentication mechanisms such as SPF, DKIM, and DMARC, along with maintaining list hygiene and crafting engaging content, are effective strategies for reducing bounce rates and enhancing email deliverability. By following these guidelines and regularly monitoring and analyzing email bounce rates, businesses can improve their email marketing effectiveness and achieve better results.

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