Simply put, an email is sent to a specific address when you send one. Responsible for getting the email is an email server. When an email cannot be delivered to a specific recipient, this server sends it back with a message explaining why. So the email bounces.
Hard bounce and Soft bounce in Email Marketing explained
What is hard bounce?
When an email cannot be delivered to the recipient’s email server due to persistent issues, it is referred to as a hard bounce. When an email fails to deliver after 72 hours, the majority of email providers handle hard bounces by immediately removing the recipient’s email address from your box.
When an email address is cleared in this way, it is either automatically removed from future email campaigns or added to a suppression list. It’s common to attempt to send an email to a rejected email server a few times again, but it’s best to stop doing so eventually as this can raise your bounce rate.
What is soft bounce?
A soft bounce occurs when an email does not reach the recipient due to transient, resolvable problems. For up to 72 hours, some email providers attempt to deliver the email in case the problem is resolved and it can eventually be automated through When your email bounces, you’ll probably get an automated message explaining why it didn’t go through, and occasionally that message will also explain what went wrong. A bounce error message usually includes the following information:
What is bounce rate and email reputation?
Your bounce rate is a statistic that shows how frequently recipients return your sent emails. Your emails are more likely to be sent successfully if the bounce rate is low. It’s crucial to keep in mind that your bounce rate affects your email reputation. Your email reputation is a gauge that evaluates the caliber of your mailing list and shows whether you are using proper email etiquette. Your emails’ bounce rates may have an impact on this data.
This information is used by Internet service providers to determine whether email recipients should accept or reject emails. Poor email reputation causes emails to frequently bounce back or automatically go into the spam folder.
For instance, a low bounce rate of 1% indicates that your mailing list is active and healthy. A bounce rate of less than 2% is considered to be acceptable in the industry. If your bounce rate exceeds 5%, you might need to find ways to reduce future bouncing.
The difference between soft bounce vs. hard bounce
The key distinction between a soft bounce and a hard bounce is that the former is a transient problem that can be resolved once the issue has been identified, whereas the latter is a failure that is permanent and cannot be remedied. Constant email bouncing can have an impact on certain background statistics, such as the email reputation rating, even though the causes of these bounces vary.
Common causes of email bouncing
The majority of email providers are unable to determine when or why an email bounced. Additionally, some internet service providers even return emails in accordance with their rating criteria and systems. You can generally identify a soft bounce vs. hard bounce based on the error code. A soft bounce is represented by a 4XX code, and a hard bounce is represented by a 5XX code. Many causes of email bouncing, regardless of the error code, are common.
Causes of soft bouncing
Some common causes of soft bouncing include:
The recipient can no longer receive any more emails if their inbox is full. This will automatically trigger an email bounce each time. If the recipient does not clear out their email inbox and make room for new emails, you will not be able to send emails to them.
When someone hasn’t checked or logged into their email for a while, it’s considered to have an inactive inbox. When an inbox is marked as inactive by the majority of email providers after an extended period of inactivity, new emails are rejected until the recipient logs back into their account.
The size of an email can occasionally cause it to bounce. The main cause of this problem is attached files because email servers have a limit on how large an attachment can be. Compressing the file will make it smaller and more deliverable, which may help you resolve the problem.
Automated content blockers block certain content presented within an email. Your email will “bounce” if it contains any content that the recipient’s email server deems inappropriate. If you can find the content that’s causing the bounce and remove it from your email, that might help.
Email server providers use DMARC, or “domain-based message authentication reporting & conformance,” as a standard for email authentication policies and reporting protocols. Based on standards established to prevent potentially unwanted emails, they employ this system to reject email messages.
Anti-virus and anti-spam programs are typically used by email recipients to keep their inboxes clear. Your email might contain something that causes their software to flag it and send it back. Your email must be received if the recipient briefly turns off their filter.
DNS stands for domain name system. When there are problems with the recipient’s DNS, this kind of bounce may happen. Although this is only a short-term problem, the time it takes to fix it can vary. Sometimes DNS servers go offline or crash for a time. Administrators usually fix this issue quickly, but it could take longer depending on the recipient’s particular domain or a server issue.
One of the most frequent reasons for emails to bounce is this. Your email may bounce back if the recipients have auto-reply or out-of-office settings, in which case you will receive the recipient’s auto-reply email in your inbox. But occasionally, your email might still be delivered and saved in a special inbox until the recipients access their email again and can read it.
Someone may have given you an incorrect email address. A typo is a frequent cause of this kind of comeback. They might have given you an email address that was misspelled, or you might have entered it incorrectly. You just need to type it in correctly to fix this problem, so it is simple to fix.
Causes of hard bouncing
Here are a few typical causes of hard bounces in emails:
Particularly if you haven’t used this email list in a while, an outdated email list will have a long list of emails that are no longer valid. Try to purge your email list of all inactive recipients to prevent hard bounces.
Your email may bounce if it is sent to a deleted email address. There are email addresses that are fake as well. The email address may no longer be accessible to send emails if the email provider has occasionally shut down.
Some email domains disappear over time, are shut down, or are moved to a different email service provider (ESP). The bounce back will occur if the domain is no longer active and all associated email addresses are also inactive. You might want to be cautious about fake domains as well.
Sometimes, the email server of the recipient may have completely prevented your emails from being delivered.
An organic email list is made up of addresses that were genuinely given to you, so email bounceback problems are likely to be avoided. It’s more likely that an email list that was bought or rented will include email addresses that are no longer valid, inactive, or just spam. Avoid using this email acquisition strategy to lower your hard bounce rate.
Tips to improve your bounce rate and email reputation
The following four suggestions should be taken into account if you want to lower your email bounce rate and reputation:
Maintain a healthy recipient list
Try to remove invalid emails on a regular basis to keep your recipient list in good shape. Maintaining a clear and active list increases your email delivery rate, which lowers your bounce rate and enhances the reputation of your emails.
Monitor your bounce rates
Track how frequently your emails bounce to keep an eye on your bounce rates. You can monitor your bounce rates daily, weekly, or as often as necessary. You can quickly correct problems by keeping an eye on your bounce rates on a regular basis before they become bigger problems. Additionally, there are online email services and software tools that you can use to track your bounce rate with ease.
Avoid questionable email addresses
Some email addresses might appear strange, inappropriate, or even fake. Try to avoid adding emails that seem unfamiliar to your mailing list.
Join a key verification registry
Email service providers (ESPs) provide their clients with a number of advantages that guarantee your emails are trustworthy and truthful. If you are a sender, you can integrate a variety of popular email authentication methods into your ESP. When you send an email, these email authenticators, also known as key verification registries, look for the accuracy of the sender address. Some common key verification registries include:
What is a soft bounce?
Usually indicates a permanent error, but a strict email security filter can also be to blame for a hard bounce. HubSpot doesn’t send emails to these contacts in the future to preserve your email sender reputation. Soft bounce: denotes a brief issue with the recipient’s server or some other brief technical issue
What does hard bounce mean?
A soft bounce in email marketing is a message that is momentarily unable to be delivered, typically due to a recipient issue. Soft bounces, or addresses that are currently unavailable but still usable, are measured in ecommerce email marketing campaigns.
Should I remove soft bounces?
A hard bounce is an email that was forwarded back to the sender due to an invalid recipient address. A hard bounce could happen if the recipient is unidentified or if the domain name is invalid.