What a Bounce Is
An email bounces when the receiving server can't or won't accept it and sends a failure notice back. Your email platform records it and, for permanent failures, usually stops sending to that address.
Bounce rate is calculated simply:
Bounce rate (%) = Bounced emails ÷ Emails sent × 100. If you send 2,000 emails and 20 bounce, your bounce rate is 1%.
Hard Bounces vs Soft Bounces
| Hard bounce | Soft bounce | |
|---|---|---|
| Meaning | Permanent failure | Temporary failure |
| Common causes | Address doesn't exist, domain doesn't exist, typo | Inbox full, server busy, message too large, temporary block |
| What happens | Address should be removed immediately | Platform retries; repeated soft bounces may become a hard bounce |
| Reputation impact | Significant if frequent | Lower, unless persistent |
What's a Normal Bounce Rate?
There's no official standard, but common rules of thumb in the email industry are:
- Total bounces under about 2% for a healthy list.
- Hard bounces well under 1%.
- A sudden jump on one send is worth investigating, whatever the number.
New, confirmed lists often have very low bounce rates. Older lists or lists that haven't been emailed in months tend to bounce more, because people change jobs and abandon addresses.
Common Causes of High Bounce Rates
- Old lists that haven't been emailed for a long time.
- Typos at signup, such as "gmial.com."
- Fake addresses entered to grab a freebie.
- Imported or purchased lists with outdated contacts. See buying email lists.
- Authentication problems, which can cause some providers to reject mail. See SPF, DKIM and DMARC setup.
How to Lower Your Bounce Rate
- Remove hard bounces immediately. Most email platforms, including AWeber, do this automatically.
- Use confirmed opt-in on forms that attract typos or fake signups. See double vs single opt-in.
- Add spam protection to forms so bots can't add junk addresses.
- Email regularly so addresses don't go stale between sends.
- Verify old lists with an email verification service before importing or re-mailing them.
- Run re-engagement campaigns and remove people who don't respond. See re-engagement email campaign.
When Bounces Signal a Bigger Problem
If bounces jump suddenly on a list that was fine before, look at the bounce messages. Rejections mentioning authentication, policy or blocking suggest a reputation or setup problem rather than bad addresses.
In that case, check your authentication, review recent changes and see email blacklist and why emails go to spam.
AWeber removes hard bounces automatically and supports confirmed opt-in, helping keep bounce rates low as your list grows.
Email Bounce Rate FAQs
What is a good email bounce rate?
A common rule of thumb is under 2% total, with hard bounces well under 1%.
What's the difference between a hard and soft bounce?
A hard bounce is a permanent failure, such as an invalid address. A soft bounce is temporary, such as a full inbox.
Should I remove soft bounces?
Not immediately. Most platforms retry, and repeated soft bounces are eventually treated as hard bounces.
Why did my bounce rate suddenly increase?
Often an old segment, an imported list or an authentication problem. Check the bounce messages for clues.