How to Reduce Your Email Bounce Rate with Email Verification | WhoisXML API

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How to Reduce Your Email Bounce Rate with Email Verification

How to Reduce Your Email Bounce Rate with Email Verification

Most online marketers have to contend with bounced email notifications from time to time. And bounced messages are marked “undeliverable” for a variety of reasons. Bounce rates vary and generally range from less than 0.4% (great) to 1.5% or more (critical), according to Klaviyo. However, specific lists may have even higher rates. Frequent email bounces don’t only reduce the effectiveness of marketing campaigns, they may eventually prevent messages from reaching their intended recipients.

Bounce Types

There are two types of bounces—soft and hard, and each can have a different effect on various email marketing metrics.

Soft Bounces

Soft bounces won’t normally have a negative impact on marketing efforts, at least in the long run. They happen as a result of temporary problems, such as full inboxes and other technical difficulties (e.g., too much traffic going to email servers). But email servers will deliver the affected messages eventually, after the problem gets fixed. That said, you need to restrain yourself from removing a subscriber from your list because of an occasional soft bounce.

Hard Bounces

While soft bounces are generally harmless and shouldn’t worry you, hard bounces can bring about serious problems. A hard bounce occurs when the email account is completely unreachable. The user could’ve blocked you from reaching it. The account may be defunct or no longer in use. The address could have been temporary and have been discarded shortly after the signup process it was used for has been completed. Or the address may have never existed, which can happen if its owner misspelled it while signing up to your page.

Improving email marketing with Email Verification

How to Reduce Email Bounce Rates: 4 Ways

There are plenty of ways to lower your bounce rates, we named at least four below with accompanying explanations. But first, let’s try to understand what an ideal bounce rate could be.

Know What’s a Good or Bad Number

While email bounce rates vary from company to company or one industry to another, you can gauge if yours is acceptable or not by comparing them with these numbers:

  • If your bounce rate is higher than 1.5% or more, you may have a serious problem with retaining readers’ attention or they send your messages straight to the spam or junk folder.
  • If it lies between 0.8% and 1.5%, your campaign is performing poorly and you need to act at once to make improvements.
  • If it is somewhere around 0.4% and 0.8%, you’re in a good place, as that is how most email marketing campaigns perform on average.
  • If your bounce rate lies below 0.4%, you’ve nailed it. This number is considered excellent in digital marketing.

Now that you know how to analyze your bounce rate, let’s talk about the ways to reduce it.

Way #1: Authenticate Your Email Domain

Having your brand imitated in phishing attacks is the fastest way to destroy your sender reputation. A possible way to reduce such risk is to enable the Sender Policy Framework (SPF) and Domain Keys Identified Mail (DKIM) authentication features. That way, cybercriminals will find it much harder to spoof or take control of your email domain, which ultimately results in poor delivery rates.

Using SPF and DKIM tells Internet service providers (ISPs) that you are who you say you are and should be trusted to send emails.

Way #2: Don’t Be Spammy

You may not know it but ISPs and email service providers (ESPs) can flag your domain and emails as spam based on the subject lines you use alone. It is, therefore, a must to avoid using what ISPs and ESPs may consider spammy terms in both your subject line and content.

Most advanced email filtering systems automatically send emails containing phrases like “as seen on,” “buy,” and “order” to clients’ spam and junk mail folders. There are, of course, tons more, which you can get from an exhaustive list of words and phrases to avoid.

While avoiding spam trigger words isn’t an exact science, ensuring that your subject lines and email content don’t oversensationalize, overpromise, and use strange formatting (making them stand out in inboxes) may be an effective way to go about this.

Way #3: Use Double Opt-In

No matter how well-crafted your marketing campaign and messages are, if the target readers aren’t interested in your products and services, they will never read your emails. A primary reason for poor deliverability is lack of interest in your offerings. That said, you need to ensure that the people you’re communicating with genuinely wish to do business with you.

Enabling the double opt-in feature on your signup pages is one way to do that. This strategy filters the truly interested out of your distribution list from the get-go.

Way #4: Use an Email Verification Tool

One of the major reasons for high bounce rates is a distribution list that is full of inactive and invalid email addresses. And while you can get rid of such email addresses manually, that process is arduous and time-consuming. Just imagine how much effort and time you’ll spend checking if every email address in your distribution list, which could contain thousands of contacts, is reachable or not.

An easier way to do it would be using an email verification tool that tells you if an email address is reachable, has a matching mail server, isn’t temporary, doesn’t point to a catch-all inbox, and isn’t invalid. Let’s look at each check in greater detail below.

  • Email address is reachable: An email verification tool uses email-sending emulation and Simple Mail Transfer Protocol (SMTP) connection techniques that tells you if an address can receive emails. An unreachable email address, when queried on Email Verification Lookup, for example, will give you this result:
Check if email address is reachable
  • Email address has a corresponding mail server: Every valid email address has a corresponding mail server that is evidenced by the presence of mail exchanger (MX) records.
Check is email address has a corresponding mail server
  • Email address is not disposable: Many users who may be guarded about their privacy sometimes use temporary or disposable email addresses to prevent marketing emails from filling up their inboxes fast. These email addresses are often discarded as soon as their owners complete the registration process they were intended for (after signup confirmation). Sending messages to temporary or disposable email addresses may ultimately cause your emails to bounce and damage your sender score. Our email verification tools can spot disposable email addresses created with Mailinator, 10MinuteMail, GuerrillaMail, and 2,000 other known disposable email service providers. 
Check if email address is not disposable
  • Email address is not a catch-all: Catch-all email addresses are meant to collect all messages sent to recipients in your company (identified by your domain) whose names may have been misspelled. They also collect the emails sent to employees who may no longer be part of an organization. However, companies can also disable this feature at some point which can lead to email bounces. Email verification tools can detect catch-all email addresses, such that you could analyze them and take further actions, like adding these emails to your inactive list, for instance. 
Check if email address is not a catch-all
  • Email address’s syntax is correct: Sending email messages to invalid email addresses is a common reason for hard bounces. Email address invalidity can have several causes, one of which is not adhering to the prescribed Internet Engineering Task Force (IETF) format. ETF requires email addresses to follow the format username@company[.]tld. A built-in syntactic email validation engine can help you identify addresses that don’t conform to IETF standards and avoid dealings with them.

Why Reducing Bounce Rates Is Important

Internet service providers (ISPs) penalize email senders who frequently send messages to accounts that produce hard bounces. If these addresses make up more than 2% of your mailing list, ISPs and other email providers may take action. They might stop all of their customers from receiving your ads or automatically send your content to the junk mail folder. Your provider could block outgoing messages from your domain as well, according to IT Pro Today.


While reducing your bounce rate isn’t a one-step process, it is doable, especially since it is a must for a business to prosper. A good bounce rate can improve your organization’s chances of reaching out to customers (existing and potential alike) in the most effective ways. It’s also worth mentioning that keeping your bounce rate within the ideal range can help you avoid the unwanted consequences of a blocked domain or one that has been blacklisted for spamming.

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