Description
Complaints, bounces, and unsubscribes all indicate the overall health and quality of your list. This article explains what these metrics mean and the rates to aim for. To diagnose and fix specific bounce types, see Resolving Email Bounces.
Why This Matters
They are a direct representation of your recipients' satisfaction with receiving your emails and affect your sender reputation.
If you regularly send engaging content to a list of people who expect to open your email, these numbers should be 0 (or very close). Every complaint or hard bounce you generate is a mark against you.
Where to find this information
You will find this information represented as totals or percentages in your campaign report, but also next to each of your contacts.
In your contact list, a few columns summarize each contact's deliverability at a glance:
- Status — the contact's subscription state: Active, Pending, Unsubscribed, or Spam. This is separate from bounces; see Contact status.
- Bounce count — how many times your sends to this address have soft bounced.
- Bounce type — what happened on the last send. None means it delivered with no bounce; otherwise it shows the reason, such as Mailbox is Full, Email Blocked, or Soft Bounce.
Hard bounce vs. soft bounce
- A hard bounce is immediate and permanent: the address is invalid, so the contact is removed from the list right away.
- Every other bounce type is a soft bounce — a temporary problem such as Mailbox is Full, Email Blocked, or Soft Bounce. The contact stays on your list and you can keep sending.
- Soft bounces add up: each one raises the Bounce count. When a single address reaches 4 soft bounces, it is treated like a hard bounce and automatically removed from the list. In other words, 4 soft bounces = 1 hard bounce.
For the full list of bounce types and how to resolve each one, see Resolving email bounces.
Bounces
A "hard" bounce: the address no longer exists (worse, maybe it never existed... Did you send a confirmation email?). If not addressed, these can have dramatic consequences for your account, sometimes even getting it suspended. As a result, all hard bounces will be removed from the list.
A "soft" bounce: the email is currently not available for a "temporary" reason. If there are 4 soft bounces on a single email address, the email address will be automatically removed from the list.
Your reports will provide you with very detailed information about your email bounces, including several different types of bounces such as: Full inbox, blocked email, or DNS failure.
Bounce rate formula:
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Expected results: 0% – 1%
Hard bounce rate should always be below 1%
Variables:
- Industry type
- How current is your list?
- How frequently do you send to your list? The more often you send, the lower the rate for each campaign
Unsubscribes
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You can expect a certain number of unsubscribes every time you send a campaign. The problem is a sudden spike. Understand that it's much better for someone to unsubscribe than to report you as spam. This has fewer consequences for your reputation.
You should expect an unsubscribe rate below 1%.
Spam complaints
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As soon as someone marks you as spam, they are permanently removed from the list.
Expected results: 0% – 0.1%
Use best practices to avoid complaints and send a test to yourself (see where it lands) before sending your campaign. Should never exceed 0.25% (1 out of 400 emails sent).
Keep in mind that ISPs look at these numbers too. If you consistently have average to critical bounce/spam levels, it's only a matter of time before your emails are sent to a recipient's junk folder and/or are permanently blocked.
Troubleshooting
High hard bounce rate (above 1%)
- Immediately review your list source - purchased lists often have high bounce rates
- Implement double opt-in to verify email addresses upon signup
- Use an email validation service to clean your list before sending
- Remove inactive subscribers who haven't engaged in 6-12 months
Sudden spike in spam complaints
- Review recent changes to your email content or frequency
- Ensure your unsubscribe link is clearly visible and working
- Check if you're following proper permission-based marketing practices
- Consider re-engagement campaigns before increasing send frequency
Soft bounces converting to hard bounces
- Monitor reasons for soft bounces (full inbox, server issues, etc.)
- Try resending to soft bounces at different times of day
- Check if certain domains are consistently soft bouncing
- Review your sending reputation with major ISPs
Unsubscribe link not working
- Test the [UNSUBSCRIBE] merge tag in preview mode
- Check that the unsubscribe page is accessible and working
- Verify if custom unsubscribe URLs are properly configured
- Ensure one-click unsubscribe is enabled for better user experience
Related Articles
- Using the suppression list - Manage unsubscribed contacts
- Understanding role-based emails - Avoid complaint triggers
- Mastering deliverability basics - Improve email delivery
- Resolving email bounces - Handle bounce issues
- Including an unsubscribe link - Compliance requirements