Email Bounce Rate: What It Is and How to Lower It
What email bounce rate means, hard versus soft bounces, a healthy benchmark, and clear steps to lower your bounce rate and protect your sending reputation.
If you send email to a list, your bounce rate is one of the numbers that quietly decides whether your messages reach the inbox. A high bounce rate tells mailbox providers that something is off, and they respond by trusting you less. The good news is that bounce rate is one of the easier problems to fix once you understand what causes it.
What is email bounce rate?
Email bounce rate is the share of your sent emails that could not be delivered and were returned by the receiving server. The formula is simple:
Bounce rate = (bounced emails ÷ emails sent) × 100
So if you send 1,000 emails and 30 bounce, your bounce rate is 3 percent. You can work out the percentage quickly with our Percentage Calculator.
Hard bounces versus soft bounces
Not all bounces mean the same thing, and the difference matters.
| Type | What it means | Typical cause |
|---|---|---|
| Hard bounce | Permanent failure | The address does not exist or the domain is invalid |
| Soft bounce | Temporary failure | Mailbox full, server down, or the message is too large |
Hard bounces are the ones to worry about most, because they point to bad addresses on your list. Soft bounces often clear up on their own, though an address that keeps softly bouncing should eventually be removed too.
What is a good bounce rate?
As a general benchmark, keep your bounce rate under about 2 percent. Many healthy senders sit well below that. Once you climb past a few percent, providers start to take notice, and a spike often means a batch of bad addresses slipped onto your list.
What causes a high bounce rate
Most bounce problems trace back to a small set of causes:
- Bad or outdated addresses, including typos and contacts that have since closed.
- Purchased or scraped lists full of addresses that never opted in and were never checked.
- No verification before sending, so guessed or old addresses go out untested.
- Weak sender setup, where missing authentication makes servers reject your mail before it even reaches a mailbox.
How to lower your bounce rate
Fixing bounce rate is mostly about list quality and setup:
- Verify addresses before you send. This is the single biggest lever. Our guide on how to verify an email address covers the checks that catch dead addresses first.
- Only email people who expect it. Permission based lists bounce far less than bought ones, and they perform better on every other measure too.
- Prefer published addresses over guesses. An address you read from a company's own contact page is far safer than a predicted pattern. A tool like our Email and Contact Extractor returns real published addresses.
- Clean your list regularly. Remove hard bounces immediately and prune contacts that have not engaged in a long time.
- Set up authentication. Make sure your domain has SPF, DKIM and DMARC records so receiving servers can confirm your mail is genuinely from you.
- Warm up new sending domains. Ramp up volume gradually rather than sending a large batch on day one from a fresh domain.
Frequently asked questions
What is a good email bounce rate? Aim to keep it under about 2 percent. Below that is healthy, and a jump above a few percent usually means bad addresses have entered your list.
What is the difference between a hard and soft bounce? A hard bounce is a permanent failure, such as an address that does not exist. A soft bounce is temporary, such as a full mailbox, and may deliver on a later try.
How do I fix a high bounce rate? Verify addresses before sending, email only people who opted in, remove hard bounces right away, and set up SPF, DKIM and DMARC for your domain.
Does bounce rate affect deliverability? Yes. A high bounce rate lowers how much mailbox providers trust you, which pushes more of your future emails toward the spam folder.
The takeaway
Your email bounce rate is a health check on your list and your setup. Keep it under about 2 percent by verifying addresses before you send, mailing only people who want to hear from you, using real published addresses rather than guesses, and authenticating your domain. Look after those basics and your good emails keep landing where they belong. Start with clean, published addresses from the Email and Contact Extractor.