Email Marketing & Klaviyo

Bounce Rate (Email)

The percentage of emails that failed to deliver, including hard and soft bounces.

1 min readLast updated Apr 2026

The percentage of emails that failed to deliver, including hard and soft bounces.

Why It Matters

High bounce rates damage sender reputation and can get your domain blacklisted. Every bounce signals to ISPs that you may be sending to bad lists, which affects deliverability for all your emails. Keeping bounces under 2% is essential for email program health.

Benchmarks

Good Performance

Under 2%

Practical Example

Scenario

A jewelry brand sends a campaign to 30,000 subscribers. 900 emails bounce.

Calculation

900 ÷ 30,000 × 100 = 3% bounce rate

Result

At 3%, they're above the 2% threshold. Analysis shows they imported an old tradeshow list without validation. After removing invalid addresses and implementing double opt-in, bounce rate drops to 0.8%.

Pro Tips

  • 1Immediately remove hard bounces—they'll never deliver and hurt reputation
  • 2Use email validation services (ZeroBounce, NeverBounce) before importing lists
  • 3Implement double opt-in to ensure valid, engaged subscribers from the start
  • 4Monitor bounce rates by acquisition source to identify problematic list segments

Common Mistakes to Avoid

Continuing to send to hard bounced addresses, compounding reputation damage
Importing purchased or rented lists without validation
Ignoring soft bounces—if an address soft bounces 3+ times, treat it as hard bounce

Frequently Asked Questions

Related Terms

Hard Bounce

A permanent delivery failure typically caused by invalid email addresses.

Soft Bounce

A temporary delivery failure caused by full inboxes, server issues, or message size limits.