Impact on the performance of email campaigns, damage to the reputation of the domain name and the SEO of the related website... hard bounce is an indicator to be monitored very closely to avoid unpleasant surprises.
#1 What is a hard bounce?
In the context of email marketing, hard bounce refers to the return of an email to the sender due to a permanent or irreversible error, most often an invalid destination address. More rarely, a hard bounce may occur if the sender's IP address has been blacklisted on suspicion of fraud or spam, or if the receiving server has been misconfigured.
The hard bounce rate, which measures the percentage of emails returned due to an incorrect or non-existent address in relation to all mailings, is an important performance indicator in email marketing, as it has a direct impact on campaign ROI.
If we're talking about a hard bounce, it's because there's also... a soft bounce. This is a temporary problem with email delivery, most often caused by a full or badly configured inbox, a problem with the recipient's mail server, an email that's too large, etc.
As a general rule, repeated and unresolved soft bounces will be transformed into hard bounces by email providers. It is therefore important not to force a sending that has produced a soft bounce before correcting the error wherever possible (file too large, for example).
#2 How to recognize a hard bounce?
Emails that don't reach their destination generally return an error email. If this refers to a permanent error (see examples), it's a hard bounce:
- Destination address does not exist
- The domain name is invalid
- The recipient's mail server does not exist.
Although they may vary depending on the server, error codes associated with hard bounces generally start with "5", and soft bounces with "4". Email marketing tools generally include hard and soft bounce counting (and real-time alert notifications) to help you monitor errors and resolve them to avoid nasty surprises... which brings us to the next question.
#3 What are the consequences of a high hard bounce rate?
Bounces, whether soft or hard, have a direct impact on the performance and ROI of your email campaigns. In retrospect, in a lead generation context, every hard bounce corresponds to an erroneous email address, with a gap between the theoretical and actual reach of your email campaign. It's also a symptom of a flaw in your data quality management. But things don't stop there.
E-mail providers (Google, Outlook, Yahoo, Zoho...) have implemented measures to limit message bounce to prevent spamming. If your campaigns show a hard bounce rate that exceeds your provider's limit, the latter will suspend your e-mail address to limit the damage. Beyond the immediate impact on your campaigns, this suspension will also affect the integrity of your company's domain name... and a blacklisted domain name will be (very) difficult to rehabilitate. If you're lucky, your emailing tool will alert you to deliverability problems before your e-mail provider takes irreversible (or hardly reversible) measures.
Also, the bad reputation of a domain name could have an impact on its natural search engine optimization (SEO). Google appears to be checking spam signals in emails sent via Gmail to identify the companies and domain names involved. Google would use this information to refine the domain name's trust index, with an impact on its visibility on the search engine's results pages.
As you can see, too high a hard bounce rate can have serious consequences for your overall performance.
#4 What is a high hard bounce rate?
As a general rule, a hard bounce rate will be qualified as "high" and potentially problematic if it exceeds 2%. Here are a few averages (hard bounces / soft bounces) provided by SendPulse :
- Food processing: 0.36% / 0.57
- Architecture and construction: 0.91% / 1.39
- B2B, finance and bancassurance: 0.46% / 0.63
- Computing and IT: 0.54% / 0.92
- Creative services and agencies: 0.70% / 1.02%.
#5 How to prevent or correct a high hard bounce rate?
Unlike open and click rates, the hard bounce rate is primarily a data problem (rather than a targeting or content problem). Here are the steps you can take to prevent or correct a high hard bounce rate:
- Implement a high-performance email validation process. We developed this point in detail in our article on the 5 most common email validation errors
- Systematically check the existence of the domain name and DNS publication authorizing emails
- Perform SMTP tests before launching email campaigns
- Check that the domain name is not blacklisted or considered spam
- Monitor email campaigns in real time to deal with bounces (soft and hard) and prevent complications
- Deploy a state-of-the-art Data Quality Management policy to ensure the reliability and freshness of your data. You can consult our guide to 5 golden rules for Data Quality to enhance overall performance.
To find out more...
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