The Key to Stopping Email Bounces

Kristen Wyatt on March 21, 2025

It’s no secret that email marketing is one of the most powerful tools to connect with your audience, build brand loyalty, and drive sales. But let’s be honest – nothing stings more than spending hours crafting the perfect email, hitting “send,” and later discovering it never reached your subscriber. This is where email bounces come into the picture. Bounces are a major factor in email deliverability. Understanding them can mean the difference between a successful campaign and one that falls flat. In this blog, we’ll explore what email bounces are, why they happen, and how you can effectively manage them to maintain a healthy sending list and improve your deliverability rates.

So – Why do bounces occur? An email bounce (or “bounce”) takes place when your email fails to reach the intended recipient’s inbox. Instead of landing in the inbox, it “bounces” back to you. Think of it as the digital version of a “return to sender” notice on a physical letter. Understanding where bounces come from is key to diagnosing and fixing deliverability issues. Bounces can stem from a variety of sources, ranging from technical problems to user behavior.

Let’s break them down into more detail:

1. Invalid or Nonexistent Email Addresses

One of the most common sources of hard bounces is sending email to addresses that don’t exist. This can happen for several reasons:

  • Typos during sign-up: A subscriber might accidentally type something like “gmaul.com” instead of “gmail.com.”
  • Deactivated accounts: The recipient might have deleted or abandoned their email account.
  • Disposable email addresses: Some users sign up with temporary addresses to access gated content, but these often expire quickly.

Consider using a double opt-in process during sign-up to tackle invalid or mistyped email addresses. This requires users to confirm their email by clicking a verification link. You can also use an email verification tool to catch typos or invalid formats before they’re added to your list. These steps will help keep your list clean and improve deliverability.

2. Domain-Related Issues

The domain (the part of the email address after the “@” symbol) can also cause bounces. Common domain-related problems include:

  • Nonexistent domains: The domain might not exist (example: user@nonexistentdomain.com).
  • Misconfigured DNS settings: The domain’s DNS records might not be set up correctly to receive email.
  • Expired domains: The domain may have expired or been deactivated.

Start by verifying domains during sign-up using an email validation tool. This ensures only legitimate, active domains make it onto your list. Regularly audit your list to remove domains that no longer exist. These steps will help keep your list healthy and reduce bounce rates.

3. Full Mailboxes

A soft bounce often happens when the recipient’s mailbox is full and can’t accept new mail. This is common with free email services like Yahoo or AOL which have storage limits.

In cases where an email cannot be delivered due to a recipient’s inbox being full, there’s little you can do immediately except wait and attempt to resend the email at a later time. If the issue persists, it’s best to remove the address from your list to keep it clean and avoid wasting resources. This approach helps to make sure your email list remains focused on active and reachable recipients.

4. Server Issues

Technical problems on the recipient’s side can also cause bounces. These include:

  • Server downtime: The recipient’s email server might be temporarily offline or undergoing maintenance.
  • Overloaded servers: High traffic or resource limitations can prevent the server from accepting new email.
  • Greylisting: Some servers temporarily reject mail from unknown senders as a spam prevention measure, but they usually accept the email on a later attempt.

For temporary issues, try resending the email after a few hours or days. Most email platforms automatically retry delivery over a set period. If the problem continues, remove the address from your list to maintain list hygiene.

5. Email Size and Content Issues

The size and content of your email can also trigger bounces. Some of the most common reasons include:

  • Large attachments: Campaigns with large attachments (over 10MB) may exceed the recipient’s server limits.
  • Spammy content: Certain keywords, excessive use of images, or poorly formatted HTML can trigger spam filters, causing the email to bounce.
  • Authentication failures: If your email lacks proper authentication (SPF, DKIM, DMARC), it may be rejected by the recipient’s server.

Start by compressing large attachments or replacing them with cloud storage links to reduce the likelihood of your email being flagged or blocked. Steer clear of spam-triggering words and phrases like “free,” “act now,” or “limited time offer,” as these can increase the chances of your content being marked as spam. Finally, confirm that your mail is properly authenticated (using protocols like SPF, DKIM, and DMARC) to verify your domain and enhance trust with email providers. These steps will help your email reach recipients’ inboxes more effectively.

6. Blocked Email

Sometimes, your mail is blocked by the recipient’s server or email provider. This can happen for several reasons:

  • IP/Domain blacklisting: If your sending IP address or domain is on a blacklist, your mail may be blocked.
  • Strict spam filters: Some organizations or email providers have aggressive spam filters that block email from unknown senders.
  • Recipient settings: The recipient may have manually blocked your email address or domain.

To resolve these issues, begin by checking if your IP or domain is listed on a blacklist using tools like MX Toolbox. If you are listed, follow the necessary delisting steps to request more information and address the underlying cause. If you’re sending email from a new domain or server, make sure to warm up your IP address gradually by increasing email volume over time to build a positive sender reputation. And encourage your subscribers to add your address to their contacts or whitelist. This can help confirm your mail consistently lands in their inboxes rather than spam folders. These proactive measures will improve your email deliverability and sender credibility.

7. Inactive or Abandoned Accounts

Over time, people stop using certain email accounts. But they may remain on your list. These accounts can lead to bounces if the provider deactivates them.

It’s important to regularly clean your lists by removing inactive subscribers who no longer engage with your email. Before taking this step, consider sending re-engagement campaigns to inactive users to give them an opportunity to reconnect with your content. If they still don’t respond, it’s best to remove them from your list. This practice improves your email engagement rates and helps to make sure your list remains focused on active and interested recipients that can positively impact your sender reputation and deliverability.

8. Role-Based Email Addresses

Role-based email addresses (for example: “info@company.com,” “support@company.com”) are often monitored by multiple people or automated systems. These addresses are more likely to bounce because:

  • They may not accept email from external senders.
  • They might have stricter spam filters.
  • They could be set up to automatically delete or reject certain types of mail.

Avoid sending marketing campaigns to role-based addresses, such as info@ or support@, unless you’re confident they are relevant and appropriate for your campaign. These addresses are often monitored by multiple people or automated systems. This makes them less likely to engage with your content. Instead, focus on targeting personal email addresses. These contacts tend to yield better engagement rates and provide more meaningful connections with your audience.

9. Seasonal or Temporary Issues

Sometimes, bounces are caused by temporary factors, such as:

  • Holiday auto-replies: Some email servers are configured to reject mail when the recipient is on vacation or has set up an auto-reply.
  • Temporary server rules: During high-traffic periods (for example, BFCM), some servers may temporarily tighten their spam filters.

If an email fails to deliver due to these issues (like having a recipient’s server being overloaded), try resending after a few days once the problem has had a chance to resolve itself.  It’s also important to monitor your bounce rates, especially during peak seasons when email servers often experience higher volumes. If you notice an increase in these bounces, consider adjusting your sending frequency or timing to reduce the strain on servers and improve deliverability.

To minimize bounces and enhance your marketing success, it’s incredibly important to take proactive steps that address the root causes. Start by using a reliable Email Service Provider (ESP) to automatically manage bounce-related issues, like retrying soft bounces and removing hard bounce addresses. Regularly monitor your sender reputation with tools like Google Postmaster or SNDS to catch and resolve potential issues early. Educate your subscribers to update their email addresses if they switch providers, helping your list to stay current. And don’t forget to test your campaigns before sending to check for size, formatting, and spam triggers. By understanding the causes of bounce issues and addressing them proactively, you can improve your email deliverability, reduce bounce rates, and position yourself so that your messages reach the right audience. Remember, a clean and well-maintained email list is the foundation of successful email marketing. So don’t skip the maintenance!

What Is Email Deliverability and Why Does It Matter?

Kristen Wyatt on January 27, 2025

Whether we’re talking to friends or running a business, email is a huge part of how we communicate. For companies, the value of email lies in its ability to reach customers. But this only works if the emails make it to their inboxes. Email deliverability is about making sure your emails don’t get blocked or sent to the spam folder. If your goal is to connect with people, understanding how deliverability works is key.

Here’s why this matters: When you send an email, you want the person to actually see it. If it ends up blocked or stuck in a spam folder, your message doesn’t get through. Good deliverability means your emails are more likely to land where they’re supposed to (which is in the intended recipient’s inbox) so more people can read them.

If your emails keep hitting spam folders, people (and email providers) might start seeing you as untrustworthy. This can result in a nasty reputation issue. But when you send emails that people actually want, you build trust and a good reputation. That makes it more likely your emails will get treated like the real deal.

Email marketing can be super effective, when it works. But if your emails don’t reach the people they’re meant for, they’re not doing much good. Making sure your emails get delivered means more people see them, engage with them, and take action.

And don’t forget, you have to play by the rules! For example, you have to make sure people actually agreed to get your emails. Ignoring rules like this hurts your deliverability. But it could get you into some real trouble, even legally. Sending emails the right way keeps you out of hot water and it helps your messages reach their audience.

Deliverability is influenced by a few main factors, starting with your reputation as a sender. Email providers keep tabs on how you’ve handled past emails – things like bounces, spam reports, and low engagement. If your track record isn’t great, it can hurt your chances of reaching your email’s intended destination. On the other hand, a solid history makes it more likely your emails will get through to the inbox.

Authorization is another big piece of the puzzle. Tools like SPF, DKIM, and DMARC help verify to email providers that you are a legitimate sender and that you’re not pretending to be someone else. Without proper authentication, your emails are more likely to get blocked or flagged.

The content in your email also matters. Misleading subject lines, too many links, overly large images, or anything that seems spammy can raise red flags. Keeping your emails simple, clear, and relevant makes them less likely to run into issues.

Your contact list plays a role too. Outdated or fake email addresses can drag down deliverability. Regularly cleaning up your active sending list and only emailing people who actually want to hear from you helps keep things on track.

Finally, how you send emails is very important. Blasting out too many too quickly or at irregular times can look suspicious. A steady, reasonable sending schedule indicates to email providers that you’re not a spammer.

How to Do It Better

  1. Watch Your Results: Keep an eye on how your emails perform. If something isn’t working, adjust your approach.
  2. Set Up Authentication: Use tools like SPF, DKIM, and DMARC so email providers know you’re a legitimate sender.
  3. Write Clearly: Avoid anything that might look suspicious to spam filters. Make your emails straightforward and relevant.
  4. Know Your Audience: Group your contacts based on what they’re interested in, so you can send emails they care about.
  5. Clean Up Your List: Remove inactive or fake email addresses to avoid bounces and complaints.
  6. Test and Adjust: Try different subject lines or formats to see what works best and keep improving.

Email deliverability comes down to making sure your messages actually reach the people you’re trying to connect with. By sticking to straightforward, honest practices and staying tuned into what works, you can ensure your campaigns hit the mark and make a real and positive impact.

Exploring the Benefits of Bounce Management

Kristen Wyatt on October 11, 2023

Email is an essential part of our lives, both business and personal. It’s a fast, convenient way to share information and conduct business. However, anyone who regularly sends emails (for marketing purposes or everyday correspondence) is likely to encounter email bounces at some point. In this blog, we will dive into all things email bounce-related: what they are, why they happen, how to manage, and ultimately prevent them.

What Are Email Bounces?

Email bounces occur when an email that you’ve sent can’t be delivered to the recipient’s inbox and is returned to the sender’s email server. This can happen for several reasons. But generally, reasons fall into two main categories: soft bounces and hard bounces.

Soft bounces are temporary issues that prevent the email from being delivered. Common reasons include a full recipient’s mailbox, a temporary server issue, or email throttling. These bounces often resolve themselves and the email may be delivered later. Hard bounces are permanent issues that prevent email delivery. These typically result from invalid/non-existent email addresses or blocking issues. When hard bounces occur, your mail won’t be delivered to the recipient.

Why Do Email Bounces Happen?

Understanding the cause of an email bounce is important for effective email management.

Here are some common reasons why bounces occur:

  • Invalid or Non-Existent Email Addresses: Sending mail to an address that doesn’t exist or has been deactivated will result in a hard bounce.
  • Full Mailboxes: If a recipient’s mailbox is overloaded, new emails will not be delivered. This will result in a soft bounce.
  • Server Issues: Temporary problems with the recipient’s email server or your email server can cause soft bounces.
  • Spam Filters: Aggressive filters may block your email, preventing it from reaching the recipient’s inbox.
  • Blacklisted Senders: If your domain or sending IP address is on a blacklist due to spam complaints or suspicious activity, your emails may bounce (common spam filter examples: Proofpoint, Mimecast, Barracuda).

Managing Email Bounces

Dealing with email bounces effectively is a must to maintain a healthy marketing campaign and reliable communication.

Here are some tips for managing email bounces:

  • Regularly Clean Your Email List: Remove invalid and inactive email addresses from your mailing list on a scheduled basis to reduce the number of hard bounces received.
  • Monitor Your Sending Reputation: Keep an eye on your domain and IP reputation to avoid being blacklisted. Follow best email practices (you can find more information on best practices here) to maintain a good sender reputation.
  • Use Double Opt-In: Implement a double opt-in process for your subscribers. Doing this ensures that addresses are valid and interested in receiving your mail.
  • Segment Your Email List: Group your subscribers based on their engagement, interests, and behavior. Send targeted content to specific segments in smaller batches to reduce the likelihood of bounces.
  • Respect Unsubscribe Requests: Honor unsubscribe Requests promptly to avoid sending unwanted mail and causing frustration (this will help to lower spam complaints).

Preventing Email Bounces

It can feel like an overwhelming task to completely eliminate bounces, but you can proactively reduce your bounce totals by putting these strategies in place. First, consider validating email addresses before adding them to your mailing list. Second, keep an eye on your bounce rates and address any spikes that exceed acceptable levels. The “best practice goal” is to keep your combined (soft and hard) bounce percentage under a total of 3%. Sending content that actively engages recipients is another key step to invite recipients to open and interact with mail which lowers the risk of being marked as spam. And last, but not least – opting for a reputable ESP (Email Service Provider) can be really beneficial. Talk to your ESP representative about accessing your bounce log details to manage bounces and maintain a positive sender reputation.

Bounces can feel like an unavoidable part of email communication. But with proper management, you can minimize their impact and maintain a healthy reputation. Remember to regularly clean your email lists, monitor your sending reputation, and follow best practices to ensure your campaigns reach their intended recipients. Doing so will enhance your email communication and achieve better overall results.