Welcome to our comprehensive guide on email hard bounce vs soft bounce. As an expert in email deliverability, I'll walk you through the differences between these two types of bounces and their impact on your email campaigns. Understanding the distinction between hard bounces and soft bounces is crucial for maintaining a healthy email list, improving deliverability, and optimizing your email marketing efforts.

What is a Hard Bounce?

A hard bounce occurs when an email cannot be delivered to the recipient's mailbox and is permanently rejected by the recipient's mail server. There are several reasons why a hard bounce might happen:

The recipient's email address does not exist or is invalid.

The recipient's email server has blocked incoming emails from your domain.

The recipient's mailbox is full or has exceeded its storage limit.The domain name in the email address does not exist.

When an email hard bounces, it is considered undeliverable, and further attempts to send emails to that address are unlikely to succeed. It's crucial to remove hard bounced email addresses from your mailing list to maintain a clean and engaged subscriber base.

What is a Soft Bounce?

A soft bounce occurs when an email cannot be delivered to the recipient's mailbox temporarily. Unlike a hard bounce, a soft bounce is a temporary issue that might resolve itself in the future. Common reasons for soft bounces include:

The recipient's mailbox is full, but it might become available once space is cleared.

The recipient's email server is temporarily unavailable or experiencing technical issues.

The email message exceeds the recipient's attachment size limit.

Soft bounces don't necessarily indicate a problem with the recipient's email address. However, if an email continues to soft bounce for an extended period, it might eventually turn into a hard bounce. Monitoring soft bounces is important to identify potential deliverability issues and take appropriate action.

Why Do Bounces Matter?

Understanding email bounces, whether hard or soft, is crucial for maintaining a healthy email list and achieving high deliverability rates. Here are a few reasons why bounces matter:

Protect Your Sender Reputation: Email service providers (ESPs) monitor bounce rates to assess the quality of your email campaigns. High bounce rates can negatively impact your sender reputation, leading to lower deliverability and potential email blacklisting.

Maintain a Clean Email List: Regularly removing hard bounced email addresses ensures that your email list only includes engaged and active subscribers. This improves overall engagement metrics and increases the effectiveness of your email campaigns.

Identify and Resolve Deliverability Issues: Monitoring bounce rates helps you identify potential deliverability issues, such as problems with your email authentication setup or domain reputation. By addressing these issues promptly, you can improve your email deliverability and ensure that your messages reach the intended recipients.

Hard Bounce vs Soft Bounce: Key Differences

Now that we've covered the basics, let's explore the key differences between hard bounces and soft bounces:

Hard Bounce

Soft Bounce

Permanent or Temporary



Delivery Status


Potentially deliverable

Action Required

Remove the email address from your list

Monitor and take appropriate action if it persists

Email address doesn't exist, blocked by recipient's server, mailbox full, or domain doesn't exist

Temporary issues like full mailbox, server unavailability, or attachment size limit

By understanding these differences, you can determine the appropriate actions to take for each type of bounce, ensuring your email campaigns remain effective and your sender reputation remains intact.

How to Handle Hard Bounces and Soft Bounces

Now that you understand the distinctions between hard bounces and soft bounces, let's discuss how to handle each type:

Handling Hard Bounces:Remove hard bounced email addresses from your mailing list immediately.

Regularly clean your email list by performing list hygiene and removing invalid or inactive email addresses.

Investigate the cause of hard bounces and take corrective actions, such as contacting the recipient to obtain a valid email address or resolving domain-related issues.

Consider using double opt-in to ensure the accuracy of email addresses during the subscription process.Handling Soft Bounces:

Monitor soft bounces closely and track their persistence over time.

If a soft bounce continues for an extended period, consider removing the email address from your list or reaching out to the recipient to verify the email address.

Check for any technical issues on your end, such as email server configuration or email content-related problems that might contribute to soft bounces.

Ensure your email campaigns comply with email best practices to minimize the chances of soft bounces.


Understanding the difference between email hard bounces and soft bounces is essential for maintaining a healthy email list, improving deliverability rates, and optimizing your email marketing efforts. By promptly handling hard bounces, removing invalid email addresses, and monitoring soft bounces, you can enhance your sender reputation, maximize email deliverability, and achieve better engagement with your target audience. Remember to regularly evaluate your email campaigns, implement best practices, and leverage email analytics to continuously improve your email deliverability.