[GTM glossary](/glossary.md) Bounce rate Sales Development & Prospecting # Bounce rate In short Bounce rate is the share of emails you send that are returned as undeliverable. It is calculated as bounced emails divided by total emails sent, usually shown as a percentage. In sales email, bounce rate is a data quality and sender reputation signal. A rising bounce rate means your list has bad addresses, and mailbox providers may begin to treat your domain as a risky sender. ## Hard and soft bounces ### Hard bounce A permanent failure, such as an address that does not exist or a domain that cannot receive mail. Remove these addresses immediately and never retry them. ### Soft bounce A temporary failure, such as a full mailbox or a server that is down. These may clear on their own, but repeated soft bounces from one address should lead to removal. --- ## How to calculate it Divide bounced emails by emails sent and multiply by 100. For example, say a rep sends 400 emails and 20 bounce. The bounce rate is 5%. Calculate it per campaign and per sending mailbox, because a single bad list can hide behind a healthy overall average. --- ## What causes high bounce rates * **Outdated contacts:** People change jobs and companies close, so old addresses stop working. * **Guessed emails:** Pattern-based guesses at addresses without verification create many failures. * **Typos and bad imports:** Manual entry and messy exports introduce invalid addresses. * **Catch-all domains:** Servers that accept all mail can look valid and still bounce later. --- ## How to reduce it * Verify addresses before sending, especially on purchased or older lists. * Start new sending domains with small volumes and increase gradually. * Suppress hard bounces automatically across all campaigns. * Re-check lists that have been idle for months. * Watch bounce rate during the first hours of a send and pause if it spikes. --- ## Bounce rate vs. other email metrics Bounce rate measures whether mail was accepted by the server. It does not say whether it reached the inbox or the spam folder, which is deliverability and inbox placement. A low bounce rate is necessary but not enough. --- ## Bounce rate FAQs **What is a good bounce rate for cold email?** Lower is better, and most teams aim to keep it as close to zero as they can by verifying addresses before sending. Rather than chasing a single benchmark, watch for sudden increases and pause sending when a campaign shows an unusual spike. **What is the difference between a hard bounce and a soft bounce?** A hard bounce is a permanent delivery failure, such as an invalid address, and should be removed from your list right away. A soft bounce is temporary, such as a full inbox or server outage, and may succeed on a later attempt. **How do you calculate email bounce rate?** Divide the number of emails that bounced by the total number sent, then multiply by 100. If 20 of 400 emails bounce, the bounce rate is 5%. Some tools count only delivered plus bounced, so check how yours defines it. **How can you lower your bounce rate?** Verify email addresses before sending, remove hard bounces immediately, avoid guessing addresses, clean old lists, and increase send volume gradually on new domains. Regularly updating contact data also helps, since people change jobs often. **Does bounce rate affect email deliverability?** Yes. A high bounce rate signals poor list quality to mailbox providers, which can lower your sender reputation. That can push future emails to spam or cause them to be blocked, even when addresses are valid. Share term --- ## More related phrases * [Soft bounce](/glossary/soft-bounce.md) * [Email validation](/glossary/email-validation.md) * [No spam](/glossary/no-spam.md) ## Similar phrases * [Email bounce rate](/glossary/email-bounce-rate.md) Email bounce rate is the percentage of sent emails that are not delivered to the recipient, and it signals list quality and sender health. * [Email verification](/glossary/email-verification.md) Email verification tests whether a specific email address is likely to accept mail, helping teams cut bounces, protect sender reputation, and avoid wasting outreach on dead addresses. * [Hard bounce](/glossary/hard-bounce.md) A hard bounce is a permanent email delivery failure, usually caused by an invalid address or domain, and it should trigger immediate removal of that address from your sending lists. * [Domain warmup](/glossary/domain-warmup.md) Domain warmup is the gradual increase of email volume on a new sending domain so mailbox providers learn to trust it and place messages in inboxes. * [Email deliverability](/glossary/email-deliverability.md) Email deliverability is your ability to get emails into recipients’ inboxes instead of spam or being rejected, shaped by reputation, authentication, and content.