What is a good overall email bounce rate?

An acceptable email bounce rate is generally considered to be less than 2%, with a particular focus on keeping hard bounces below 1%. While soft bounces are temporary, a consistently high soft bounce rate can also indicate underlying issues affecting your sender reputation and deliverability.

What is the key difference between a hard and soft bounce?

A hard bounce is a permanent delivery failure, meaning the email address is invalid or no longer exists. You should immediately remove these addresses from your list. A soft bounce is a temporary delivery issue, such as a full inbox or server problem, and the email service provider (ESP) will typically retry sending.

Do email bounces affect my sender reputation?

Yes, hard bounces significantly impact your sender reputation because they signal poor list quality to ISPs. Consistently sending to invalid addresses can lead to your domain or IP being blocklisted . While individual soft bounces are less damaging, a high volume of them over time can also signal issues that negatively affect your deliverability.

Should I resend emails to bounced addresses?

For hard bounces, absolutely not. They are permanent failures. For soft bounces, your ESP will usually retry automatically. If an email repeatedly soft bounces, it's generally not recommended to keep retrying manually; instead, it's best to suppress that address to avoid damaging your sending reputation.

How can I reduce my email bounce rate?

To reduce bounce rates, regularly clean your email list by removing hard bounces, use email validation services for new contacts, implement double opt-in, and segment your audience to send highly relevant content, improving engagement and reducing chances of being marked as spam. For more tips on managing hard and soft bounces , consider best practices.

What is an acceptable email bounce rate, and how do hard and soft bounces differ? - Basics - Email deliverability - Knowledge base

Email bounces are an unavoidable part of sending emails, but understanding them is crucial for maintaining a healthy sender reputation and ensuring your messages reach their intended recipients. When an email fails to deliver, it's categorized as a bounce, signaling an issue that needs attention.

Not all bounces are created equal. They fall into two primary categories: hard bounces and soft bounces. Each type has distinct implications for your email deliverability and requires a different approach to management.

In this article, I'll clarify what constitutes an acceptable email bounce rate, differentiate between hard and soft bounces, and provide strategies to keep your bounce rates low, safeguarding your sender reputation.

Understanding hard bounces

The email bounce rate is the percentage of emails that could not be delivered to the recipient's inbox. A high bounce rate indicates potential issues with your email list quality or sender reputation, which can negatively impact your ability to reach subscribers.

A general benchmark for a healthy email bounce rate is less than 2%. This figure primarily pertains to hard bounces, as soft bounces are temporary and typically do not count against this benchmark in the same critical way. Maintaining a bounce rate below this threshold is essential for a good sender reputation.

However, it's important to recognize that acceptable bounce rates can vary across industries. For example, sectors with frequent changes in professional contact information, such as healthcare, might experience slightly higher bounce rates due to email addresses becoming obsolete more rapidly. Always consider your specific industry context when evaluating your bounce rate.

Hard bounces

Hard bounces represent a permanent delivery failure. This means the email address is invalid, non-existent, or permanently blocked. When an email hard bounces, it indicates that the message will never be successfully delivered to that specific address.

Common reasons for hard bounces include a misspelled email address, the recipient's domain no longer existing, or the recipient's server permanently blocking your emails due to spam complaints or spam traps. These permanent failures are the most damaging to your sender reputation.

Upon receiving a hard bounce, it is critical to immediately remove the problematic email address from your mailing list. Continued attempts to send to a hard bounced address will significantly harm your sender reputation and could lead to your emails being blocklisted (or blacklisted) by internet service providers (ISPs).

Understanding soft bounces

Soft bounces, unlike hard bounces, indicate a temporary email delivery issue. The recipient's email address is valid, but the message couldn't be delivered for a transient reason. This could include a full inbox, the recipient's server being temporarily down or offline, or the email message being too large.

Most Email Service Providers (ESPs) will attempt to resend soft bounced emails several times over a period, hoping the temporary issue resolves itself. If the issue persists after multiple attempts, some ESPs may eventually treat it as a hard bounce and remove the address from your list. For a more detailed explanation, Mailchimp offers a helpful resource on soft vs. hard bounces.

While individual soft bounces don't have the same immediate negative impact as hard bounces, a consistently high rate of soft bounces can signal underlying problems. This might include issues with your sending infrastructure, poor engagement from your audience leading to emails going to spam, or general deliverability challenges.

Hard bounces

Definition: Permanent delivery failure.
Cause: Invalid email address, non-existent domain.
Impact: Immediately damages sender reputation. Can lead to blocklisting.
Action: Remove from list immediately. Do not resend.

Soft bounces

Definition: Temporary delivery issue.
Cause: Full inbox, server downtime, message too large.
Impact: Minor individual impact, but consistent soft bounces can signal broader deliverability issues.
Action: Monitor and allow ESP to retry. If persistent, investigate and consider removal.

Managing bounces and maintaining deliverability

Effective bounce management is vital for successful email marketing. Here's how to manage both hard and soft bounces to protect your sender reputation and maximize your inbox placement.

List cleaning: Regularly remove hard bounced email addresses from your mailing list. Many ESPs automatically handle this, but it’s good practice to verify.
Validation: Use email validation services before sending to new contacts to minimize initial hard bounces. This is especially useful for older lists.
Monitoring: Keep an eye on your soft bounce rates. A sudden spike or a persistently high rate indicates potential issues that warrant investigation, such as a deliverability problem.
Engagement: Focus on sending relevant content to engaged subscribers. Low engagement can signal to ISPs that your emails are not valued, leading to more bounces or blocklisting.

For persistent soft bounces, especially those not clearing after multiple retries, consider a soft bounce suppression logic. If an address repeatedly soft bounces, it might be an indication that the email address is effectively defunct or problematic, even if not permanently invalid. Removing such addresses can prevent them from impacting your overall deliverability negatively.

Views from the trenches

Best practices

Maintain a hard bounce rate of 1% or lower to protect your sender reputation and avoid blocklisting.

Regularly clean your email lists by removing invalid or non-existent email addresses immediately after a hard bounce.

Monitor your soft bounce rates closely, investigating any sudden spikes or sustained elevated levels as these can indicate underlying deliverability issues.

Implement a clear suppression strategy for email addresses that consistently soft bounce over a defined period.

Focus on acquiring opt-in contacts to ensure a higher quality list and reduce the likelihood of bounces.

Common pitfalls

Ignoring hard bounces and continuing to send emails to invalid addresses, which severely damages sender reputation.

Failing to monitor soft bounces, missing early warning signs of deliverability problems or potential blocklistings.

Sending emails to purchased or old lists without prior validation, leading to high bounce rates and spam complaints.

Not considering industry-specific nuances when evaluating bounce rates, as some sectors naturally experience higher churn.

Over-reliance on automatic bounce handling by ESPs without understanding the underlying causes or verifying their effectiveness.

Expert tips

There is no single industry standard definition for hard and soft bounces, as ISPs may classify them differently.

Repeated soft bounces can eventually be recorded as hard bounces by some sending servers, indicating potential reputation problems.

Even if your overall soft bounce rate is low, a significant spike may signal a temporary issue with a specific receiving server.

In industries with high contact turnover, such as healthcare, frequent email address changes can lead to higher bounce rates, requiring more proactive list maintenance.

Manually looking up updated contact information for bounced emails is not scalable for large lists and can be highly inefficient.

Expert view

Expert from Email Geeks says that the 2% bounce rate ceiling generally applies to hard bounces only, as soft bounces are a normal part of sending. He added that a target for "bad address" hard bounces should be 1% or less, noting that repeated soft bounces can sometimes be recorded as hard bounces.

2019-12-04 - Email Geeks

Marketer view

Marketer from Email Geeks explained that soft bounces are more complex and situational than hard bounces. He advised looking into spikes or sustained elevated soft bounce rates.

2019-12-04 - Email Geeks

Improving your email deliverability through bounce management

Effectively managing email bounces, whether hard or soft (or even those on a blacklist), is fundamental to maintaining high email deliverability. By understanding the nuances between permanent and temporary delivery failures, you can implement strategies that keep your email list clean, protect your sender reputation, and ultimately ensure your marketing messages consistently reach the inbox.