Hard Bounce vs. Soft Bounce: These Are The Differences

If an email is not delivered, this is referred to as a bounce. In email marketing, a distinction is made between soft bounces and hard bounces. Read here what the differences are and what you can do to counteract high bounce rates.

Written by Hannah Krüger

Why Are My Emails Not Being Delivered?


Wondering about low engagement rates? Your open and click rates are pretty low despite exciting content? The reason may be easier than you think. Your emails aren't getting delivered in the first place - they're bouncing. This makes engagement rates look meager because your recipients aren't receiving your emails in the first place. When this happens, you automatically get a message from the relevant email service provider (ESP). With the help of the so-called bounce message, you can find out which recipient is affected, which newsletter it is and why the email bounces. 

Bounces are an important part of your email metrics. Almost all newsletter editors or analysis tools track your bounces. JUNE also shows you your bounces after sending campaigns. The fact that an email is not delivered happens with almost every newsletter dispatch. So don't worry about individual bounces.  

Basically, we distinguish between hard bounces and soft bounces. 


Hard Bounce

There is a permanent reason why an email cannot be delivered. If a hard bounce occurs, the recipient's email address is automatically removed from the recipient list. Thus, future campaigns will not be sent to the affected recipient.


Reasons for hard bounces 


  • The recipient's e-mail address does not exist (e.g. due to a typing error).
  • The recipient's e-mail server has blocked delivery 

Soft Bounce

There are temporary reasons why a mail is not delivered. This means that delivery may be possible again in the future. The recipient's email address remains in your sender list, so you can continue to send campaigns to the address. However, soft bounces can be converted to hard bounces if an email address has experienced multiple soft bounces in a row. The number varies depending on the provider and is approximately between 3 and 20 soft bounces. 

Reasons for soft bounces


  • Recipient's mailbox is full 
  • Recipient's mailbox is inactive 
  • E-mail message or e-mail content is too large (e.g., too many images)
  • E-mail content is blocked
  • Recipient's e-mail server is down or offline 
  • Email content does not meet the email server's anti-spam requirements (“content bounce”)

How To Minimize Bounce Rates

It's important to keep an eye on your bounce rates. High bounce rates can lead to a bad reputation and hurt your overall delivery. You can combat high bounce rates with a few tips and tricks.


  • Make sure you enter email addresses correctly, especially if you add them manually.
  • Find out about spam triggers. Even single words will send your mail to the spam folder.
  • Keep your recipient lists up to date. Re-subscribing may shrink your audience. However, their engagement rates will skyrocket as they send their campaigns exclusively to those who are interested. Email addresses that trigger soft or hard bounces will be removed. So don't be afraid to weed out inactive contacts. 

JUNE Takes Care Of Your Bounces

Generally, hard bounces are immediately removed from recipient lists. JUNE handles hard bounces a little differently. We turn a blind eye to them. Hard bounces do not only occur when an invalid email address is involved. A newsletter can also bounce hard due to technical problems. Sometimes these problems can be solved. JUNE will take care of this internally as soon as you experience a hard bounce. However, if we cannot solve the technical problem or if there are multiple bounces, the affected email address will be removed. 


With the dashboard, you always have an overview of your bounces. After sending campaigns, you can see your bounce rate in real time. Manage your email lists with our automation module and remove the contacts who don't interact with their campaign content. 


Spam traps: what is important to know