What is a reasonable soft bounce tolerance in email marketing?
Matthew Whittaker
Co-founder & CTO, Suped
Published 23 May 2025
Updated 13 Oct 2025
6 min read
In email marketing, managing bounce rates is crucial for maintaining a healthy sender reputation and ensuring your messages reach the inbox. While hard bounces are permanent failures and should be removed immediately, soft bounces are temporary issues that require a more nuanced approach. The key lies in establishing a reasonable soft bounce tolerance, a threshold after which a temporarily undeliverable address is treated with more caution.
Understanding this tolerance helps you balance perseverance with prudence, giving legitimate emails a chance to get through without harming your long-term deliverability. It is about knowing when to retry and when to stop to preserve your sender reputation.
Understanding soft bounces
A soft bounce occurs when an email reaches the recipient's mail server but is rejected before it lands in the inbox. This is distinct from a hard bounce, which indicates a permanent delivery failure, like an invalid email address. Common reasons for soft bounces include a full inbox, an unavailable server, or the message being too large. These are often temporary problems that might resolve themselves over time. For more on the distinction, Mailchimp provides a clear explanation of soft vs. hard bounces. Mailchimp explains this clearly.
However, even though they are temporary, a high volume of soft bounces can still signal issues to Internet Service Providers (ISPs) and impact your sender reputation. ISPs might interpret repeated soft bounces as a sign of a poorly maintained list or even spam-like behavior, leading to your emails being directed to spam folders or blocklisted (blacklisted). It is why proactive management of these bounces is essential.
The key is to differentiate between an actual temporary issue and an address that is persistently soft bouncing, which might indicate a deeper problem. Ignoring these persistent soft bounces can negatively affect your email deliverability and sender reputation, potentially leading to lower inbox placement rates across your entire list.
Establishing a soft bounce tolerance
When it comes to setting a reasonable soft bounce tolerance, there is no one-size-fits-all answer. Many Email Service Providers (ESPs) have their own default settings. For instance, some platforms might allow up to seven consecutive soft bounces for a given email address before it is automatically suppressed. This number feels reasonable to many in the industry, offering a good balance between persistence and prudent list management. However, what constitutes an acceptable email bounce rate can also depend on your industry and list hygiene.
The critical factor is that this tolerance typically refers to consecutive soft bounces for a specific email address across different sends, not multiple bounces within a single send. This distinction is vital for understanding how your ESP (or your own system) manages these events. You also need to consider the timeframe over which these bounces occur. Seven bounces over seven days is different from seven bounces in one day.
Generally, an overall email bounce rate of less than 2% is considered good, with soft bounce rates ideally remaining below this figure. For a deeper dive into industry standards, AgencyAnalytics suggests a good soft bounce rate is typically below 2%. Ultimately, the best practice is to define a clear soft bounce suppression logic that aligns with your sending frequency and audience engagement.
Impact on sender reputation and deliverability
The silent threat to your sender reputation
While hard bounces are obvious red flags, a consistent pattern of soft bounces, even if individually temporary, can collectively damage your sender reputation. ISPs closely monitor your bounce rates. If they see a high proportion of your emails consistently failing to reach inboxes, even due to temporary reasons, it can negatively affect how they perceive your sending practices. This could lead to your emails being filtered as spam, or even worse, your IP address or domain being placed on an email blocklist. Maintaining a healthy email domain reputation is paramount for effective email marketing.
This impact on sender reputation directly translates to lower email deliverability. If ISPs distrust your sending domain, fewer of your emails will make it to the primary inbox, reducing engagement and the effectiveness of your campaigns. It can be a slow, insidious decline that is hard to recover from without proactive measures. This emphasizes the importance of understanding not just what a soft bounce is, but also its broader implications for your email program.
Effectively managing soft bounces requires constant vigilance. It means not only setting a tolerance but also having the tools to monitor and analyze your bounce data to identify trends and potential problems early on. A well-managed bounce strategy protects your reputation and maximizes the reach of your email communications.
Best practices for managing soft bounces
Proactive strategies
Segment your audience: Send to engaged subscribers to reduce the likelihood of full inboxes.
Validate email addresses: Use validation services at point of collection to minimize invalid addresses. Check your bounce rates after email validation to ensure effectiveness.
Warm up new IPs/domains: Gradually increase sending volume to establish trust with ISPs.
Monitor DMARC reports: Gain visibility into bounce rates and authentication issues across all sending sources.
Reactive strategies
Implement suppression logic: Automatically suppress emails after reaching your defined soft bounce tolerance. This is a best practice for managing soft bounces in daily campaigns.
Periodically clean lists: Remove inactive or consistently bouncing addresses to improve list hygiene.
Analyze bounce codes: Understand the specific reasons for soft bounces to address underlying issues.
Adjust sending frequency: Reduce mail volume to addresses that frequently soft bounce.
The implementation of these best practices is essential for any sender looking to maintain high deliverability. It is a continuous process that involves both strategic planning and day-to-day operational adjustments. Regularly reviewing your email performance metrics will provide the insights needed to refine your approach.
Remember that consistency and attention to detail will yield the best results. A healthy email list is a valuable asset, and protecting it from the negative effects of unmanaged bounces should be a top priority. This proactive management also involves knowing how many soft bounces before suppressing a user to keep your list clean and effective.
Maintaining a healthy email list
Ultimately, a reasonable soft bounce tolerance is a dynamic measure. It should be aggressive enough to prevent long-term damage to your sender reputation but flexible enough to account for temporary network issues. Continuous monitoring of your email performance, coupled with a well-defined suppression strategy, is the most effective approach.
The goal is to foster a healthy email ecosystem where your messages reliably reach engaged recipients, ensuring the continued success of your email marketing efforts. Suped offers robust DMARC reporting and monitoring tools to provide the visibility you need to manage bounces effectively and safeguard your deliverability.
Views from the trenches
Best practices
Actively monitor your bounce rates, specifically segmenting soft and hard bounces to identify trends and address underlying issues promptly.
Implement automated suppression logic in your ESP to automatically remove or suppress email addresses after a set number of consecutive soft bounces.
Regularly clean your email lists by removing inactive subscribers and those who consistently soft bounce to maintain high list hygiene and improve deliverability.
Utilize email authentication protocols like DMARC, SPF, and DKIM to bolster your domain's reputation and ensure that legitimate emails are recognized by ISPs.
Focus on acquiring high-quality leads and use email validation at the point of entry to minimize invalid or problematic email addresses from entering your list.
Common pitfalls
Ignoring persistent soft bounces, which can lead to a degraded sender reputation and increased chances of being blocklisted (blacklisted) by ISPs over time.
Aggressively re-sending emails to addresses that repeatedly soft bounce without a clear strategy, which can be interpreted as spamming behavior.
Failing to understand the difference between soft and hard bounces, leading to incorrect list management decisions and continued deliverability problems.
Not considering the 'over time' dimension of soft bounces, such as a high number of consecutive bounces within a short period, which is more critical.
Overlooking bounce codes and not analyzing them to understand the root causes of delivery failures, thus missing opportunities for targeted remediation.
Expert tips
Set your soft bounce tolerance to around 5-7 consecutive bounces before suppressing the address, but adjust based on your sending frequency and audience engagement.
Leverage DMARC reports to get a holistic view of your email authentication and delivery, including detailed insights into bounce events and their sources.
Educate your team on the nuances of bounce management and the critical role it plays in overall email deliverability to ensure consistent application of best practices.
Consider temporary suppression for specific soft bounce reasons like 'mailbox full' and retry after a few days, but permanently suppress after multiple failures.
Review ISP feedback loops if available, as these can provide direct insights from mailbox providers regarding how they perceive your sending practices.
Marketer view
Marketer from Email Geeks says Klaviyo, an ESP, uses a policy of seven consecutive soft bounces before an email address is suppressed.
May 31, 2019 - Email Geeks
Expert view
Expert from Email Geeks says a bounce tolerance of seven consecutive soft bounces seems reasonable for managing email lists.
