Email Hard Bounce v Soft Bounce and How to Reduce Them

Content by: Heather Scaglione from EasyDMARC

Email bounces are a common but often overlooked issue that can quietly damage your deliverability and sender reputation. Whether you’re sending newsletters or running marketing campaigns, understanding why emails fail to deliver is essential to keeping your messages out of spam folders and in inboxes.

Not all email bounces are the same. Some are temporary and resolve on their own, while others signal permanent problems that prevent future delivery. Knowing the difference between a hard bounce and a soft bounce helps you identify issues early, clean your mailing list, and reduce bounce rates to improve overall performance.

In this guide, we’ll explain how each type of bounce works, why it happens, and what you can do to prevent bounces from hurting your campaigns.

What Is a Soft Bounce?
A soft bounce occurs when an email can’t be delivered due to a temporary issue. Common causes include a full mailbox, a temporarily unavailable mail server, or an email that exceeds size limits. Technically, the receiving server rejects the message without marking it as permanently undeliverable.

For example, if a subscriber’s inbox is full, your email may bounce once but go through later when space is cleared. Understanding soft bounces helps you determine whether an issue is temporary or a sign of a larger deliverability problem.

What Is a Hard Bounce?
A hard bounce means your email has been permanently rejected. This typically happens when an address doesn’t exist, the domain is invalid, or your sending domain is blocked. These failures return 5xx error codes, such as 550, and cannot be retried.

High hard bounce rates are a clear sign of poor list hygiene and can seriously harm your sender reputation over time.

9 Ways to Reduce Email Bounces
Lowering bounce rates is critical for strong deliverability and long-term trust. Key best practices include:

• Authenticating your email with SPF, DKIM, and DMARC

• Building your list organically through opt-ins

• Regularly cleaning and verifying your contacts

• Avoiding spam-triggering content and formatting

• Segmenting your list for better engagement

• Sending on a consistent schedule

• Monitoring bounce reports closely

• Using a domain-based email address

• Collecting data carefully with form validation

Deliverability Starts With Trust
Reducing hard and soft bounces isn’t just about clean lists—it’s about building credibility with mail servers and sending emails people actually want. When you focus on authentication, engagement, and data quality, deliverability improves naturally.

Start protecting your sender reputation today with EasyDMARC’s 14-day free trial and keep your emails landing where they belong: the inbox.