Email bounce rate is one of the key metrics that needs to be monitored for a successful email campaign. You can use dedicated IPs and the right warm-up plan to increase your deliverability; but bounces can ruin you reputation.
In a layman's term, an email is termed as a bounce back if it is not delivered to its intended recipient. An email bounces back due to some common reasons like the change of job, abandonment of an email account, changing ISPs. It is required by all email marketing service providers to keep the bounce rate in check.
The acceptable bounce rate (the email bounce rate threshold) is approximate 3% to 5% but does vary for every service provider. Your account may get blocked if you have hard bounce rate above 10% in most of ESPs.

An email campaign report showing the bounce rate - eSputnik Marketing Automation Software.
Why Does Your Email Bounces?
If your well-planned email campaign is flooded with high bounce rates, here are some checking points to be considered. ASAP!
Errors in imported list
Majority of the email marketing services accepts CSV format to import an email list. .CSV files need to be properly formatted if you see incorrect information in the email address field.
Sending emails by free email providers
DMARC authentication will be failed if you are sending emails through a free email provides like Yahoo or Gmail. The updated DMARC policies by the majority of the email providers require an email to be sent from private domains.
Mailing to an old email list
One of the key metrics of email marketing is to send out emails on regular basis. If you are mailing to a long-acquired email list there are high chances that some of the email addresses have been abandoned or have been converted into recycled traps due to inactivity by the inbox providers.
Un-hygienic email list
Quality over quantity is best suited for email marketing and email list as well. It is the quality of an email list accelerates an email marketing campaign. Using a scraped or purchased email list needs to be checked for its quality before you start paying for email marketing.
Type of Email Bounces & What Does it Mean?
Soft bounce = Temporary delivery failure
A soft bounce occurs when your email got as close as the receiving mail server (the email accounts is recognized) and does not make it to the inbox. Here are a few reasons for the soft bounce.
- The receivers mailbox is full
- Message size is too large
- You are being blocked by the recipient
- your content shouts spam
Hard bounce = Permanent delivery failure
Hard bounce needs the most attention in your email list as it is a permanent failure and harms your sender's reputation every time you attempt to mail to such invalid addresses. You can read Hard Bounces versus Soft Bounces in order to obtain a better understanding of difference between soft and hard bounces. Here are a few reasons for the hard bounce.
- Invalid email account
- No registered mail servers
- Typos (Yahooo instead of Yahoo)

Hard and soft bounce differences.
How to Deal With Email Bounces?
The alarming bounces from your campaigns need immediate attention. High bounces rates not only lead to account suspension but harms the marketing outcome as well. Here are the key steps to pull back your email bounces before you are up and running again. In case you want to find a someone's valid email address and you have its first name, last name and where he/she works, you can use DropContact.
Use the double opt-in list
A double opt-in process is where the user needs to click on email verification link before they are added to the list. A double opt-in can fight a lot of fake sign-ups also it assures that the email is valid and the inbox is being monitored.
Keep your email list clean
Not cleaning an email list will always result in the bounces beyond specified limits. Higher bounces will have a temporary account ban (In some cases permanent) by email marketing services. Here is the benefits of a clean email list.
Don't sound like a spammer
ISPs and inbox providers like Yahoo & Gmail have built-in advanced spam filters, an email is sent through the filters. The filter checks the message for anything spammy and sends email to spam box if anything is out of ordinary.
Send email regularly
The tried and tested approach is sending out emails at least twice a month. The high volume marketers with awesome copies and regular offers popping up send out emails two to three times a week. But don’t forget to keep an eye on the performance of email campaigns at all times.
Removing bounces using DeBounce
The most effective method in order to remove bounces is to use email validation services. DeBounce can easily remove bad and invalid emails from your lists with accuracy of +97.5%. Sign up on DeBounce, upload your list and start removing bounce emails from your list to prevent deliverability issues.
SMTP routing
SMTP routing is a very handy feature offered by Pabbly Email Marketing that can help you tackle bouncing emails. Using this feature, you can divide your long list of subscribers into smaller slots and then send emails to each slot via multiple SMTP servers. Sending emails to smaller lists of subscribers avoids overloading on the server which in turn reduces email bounce. Further, it also reduces spamming of your emails and improves their deliverability.