Bounce
Learn what causes email bounces, the difference between hard and soft bounces, and how DMARCeye helps identify and prevent authentication-related issues.
What Is a Bounce
A bounce occurs when an email message cannot be delivered to the recipient’s inbox and is returned to the sender’s mail server.
Bounces are a normal part of email communication, but a high bounce rate can signal deeper issues such as poor list hygiene, misconfigured authentication, or blocked sending reputation.
Each bounce message includes a short explanation, often in the form of an SMTP error code, that helps identify the reason for the failed delivery.
Types of Bounces
There are two main types of bounces: hard bounces and soft bounces.
Hard bounces are permanent delivery failures. They occur when an email address doesn’t exist, the domain is invalid, or the recipient’s mail server completely rejects the message. These addresses should be removed from mailing lists to maintain sender reputation.
Soft bounces are temporary delivery issues, such as a recipient’s inbox being full, the mail server being temporarily unavailable, or the message being too large. Soft bounces may succeed later, but repeated soft bounces can eventually become hard bounces.
Why Bounces Are So Important for Business
Bounces directly impact email deliverability and sender reputation. Mail providers monitor bounce rates to determine whether a sender is trustworthy. High bounce rates can trigger spam filters or cause mail to be rejected.
Consistent bounce monitoring helps identify problems early, such as invalid recipients, misconfigured DNS or authentication records, or blocked IP addresses. Maintaining a clean mailing list and using proper authentication are essential for keeping bounce rates low.
Bounces and DMARCeye
Bounces are more than just delivery issues; they can be a sign of authentication failures or DMARC policy misconfigurations.
DMARCeye helps organizations identify the root cause of such failures by analyzing DMARC reports, authentication results, and sender behavior. If an email fails SPF or DKIM checks and doesn’t align with your DMARC policy, some mail servers may bounce or quarantine it.
By tracking these results visually, DMARCeye gives teams the insight needed to correct DNS or policy errors before they harm deliverability or reputation.
Sign up for a free trial of DMARCeye today to secure your email domain.
To learn more about DMARC and DMARC-related terms, explore the DMARCeye Glossary.