You send a campaign to 1,000 contacts. Three emails soft bounce. Your Email Soft Bounce Rate is 3 / 1,000 = 0.003, or 0.3%. A rate this low is healthy. If the same addresses soft bounce across multiple campaigns, consider suppressing them to protect your sender reputation.
Email Soft Bounce Rate
Last updated: Jun 08, 2026
What is Email Soft Bounce Rate?
Email Soft Bounce Rate is the percentage of sent emails that fail to reach the recipient due to a temporary technical issue, such as a full inbox or an unavailable mail server.
Email Soft Bounce Rate Formula
ƒ Count(Email Soft Bounces) / Count(Emails Sent)
How to calculate Email Soft Bounce Rate
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What is a good Email Soft Bounce Rate benchmark?
Soft bounce rates below 2% are generally considered healthy for well-maintained lists. Rates between 2% and 5% warrant monitoring. Rates above 5% suggest list quality or deliverability issues that need attention. Benchmarks vary by industry, list age, and sending volume.
How to visualize Email Soft Bounce Rate?
Use a line chart to visualize your email bounce rate data over time. This lets you quickly identify any anomalies in behavior which you can then rectify.
Email Soft Bounce Rate visualization example
Email Soft Bounce Rate
Line Chart
Here's an example of how to visualize your Email Soft Bounce Rate data in a line chart over time.
Email Soft Bounce Rate
Chart
Measuring Email Soft Bounce RateMore about Email Soft Bounce Rate
What causes a soft bounce?
Several temporary conditions trigger a soft bounce. The most common include:
- Full inbox: The recipient's mailbox has reached its storage limit and cannot accept new messages
- Server temporarily unavailable: The receiving mail server is down or experiencing issues at the time of delivery
- Message too large: The email exceeds the size limit set by the recipient's mail server
- Auto-reply or vacation message: Some mail servers return a soft bounce code when an out-of-office reply is active
- Greylisting: A spam-filtering technique that temporarily rejects messages from unknown senders, expecting legitimate senders to retry
Most email platforms retry soft bounces automatically over a set period — typically 72 hours. If delivery still fails after retries, the address may be flagged as a hard bounce.
What is a good email soft bounce rate?
Soft bounce benchmarks vary by industry, list size, and email platform. As a general guide:
| Soft bounce rate | Assessment |
|---|---|
| Below 2% | Healthy — typical for well-maintained lists |
| 2%–5% | Monitor — investigate list quality and sending infrastructure |
| Above 5% | Concerning — review list hygiene, sending frequency, and server reputation |
These ranges are indicative, not universal. High-volume senders and those emailing cold or older lists will see higher rates. Always compare your rate against your own historical baseline, not just industry averages.
Why email soft bounce rate matters
A rising soft bounce rate is an early warning sign. Left unaddressed, it can damage your sender reputation with inbox providers like Gmail and Outlook, which in turn reduces deliverability for your entire list — not just the bouncing addresses.
Tracking soft bounce rate alongside Email Hard Bounce Rate gives you a complete picture of list health. Soft bounces point to temporary friction; hard bounces point to permanent problems. Together, they tell you where to act.
How to reduce email soft bounce rate
A few targeted practices keep soft bounce rates low:
- Use double opt-in: Confirming each subscriber's address at signup reduces invalid and mistyped entries before they reach your list
- Clean your list regularly: Remove addresses that have soft bounced repeatedly across multiple campaigns — they are likely to become hard bounces
- Monitor sending frequency: Sending too frequently can trigger spam filters or overwhelm servers, contributing to soft bounces
- Check email file size: Keep image-heavy emails within common server size limits (typically under 100 KB for the HTML body)
- Warm up new sending domains: Gradually increasing send volume from a new domain reduces the chance of greylisting and server-level rejections
- Review bounce codes: Most email platforms provide bounce reason codes. Use them to distinguish inbox-full bounces from server-level issues — the response is different for each
Repeated soft bounces from the same address should prompt removal or suppression. An address that soft bounces across three or more campaigns is unlikely to become a reliable recipient and risks pulling your sender score down.
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