November 19th, 2019 | by

Welcome to another Whiteboard Wednesday! I’m Brad Owen, CEO and Owner of Neverbounce, an email verification and list-cleaning tool that was acquired by DiscoverOrg and ZoomInfo in February 2019. And I’m happy to be here today with DiscoverOrg, to drop some truth bombs about email deliverability – that you might not know!

Let’s jump in.

I’m often asked how to use the results from the email verification process. A lot of people think, “Hey, I am sending out my campaigns. There is no issue.”

But the fact is – unless you are taking some sort of a proactive approach to email deliverability – there probably is a problem.

Let’s take a closer look at email deliverability.

Your email deliverability is lower than you think

To most people, the email inbox deliverability equation looks something like this:

I send out 1000 emails, and 10% – or 100 – bounced. I have 90% email deliverability.

And most people would be right … without more information.

When we’re looking at our email service providers, we’re seeing click-through rates, we’re seeing open rates – but we don’t see an inbox rate.

If over 10% of the emails you send bounce, less than 40% are actually delivered to the inbox – based on a recent study, and Neverbounce’s internal research.

That has a huge effect on your actual deliverability! If 10% of these emails are bouncing, instead of 90% deliverability, we’re actually looking at 60% deliverability.

And 60% deliverability is pretty awful.

Read it: What is SPAM? The Truth About Cold Email

Is anyone home? Email verification rings the doorbell

So how do you fix the deliverability issue? Introducing email verification!

Email verification is the process of going out to a remote server to identify whether the email is valid or invalid. In doing so, we are speaking directly to a remote server and identifying whether that email is good to send.

We get different codes back in response, and classify them into different buckets.

To understand the response to email verification, let’s use the analogy of a home address:

The individual’s name is the first part of the address – Let’s say it’s John. The second part of the email, the domain name, is comparable to the street address.

DO SEND TO: Hello, the owner is home

Connecting to the email server is just like walking up to the front door of a home: We’re going to knock and ask, “Hey, is John home?” If John answers the door, we know 100% it’s a valid address. No problem.

DON’T SEND TO: Someone (else) is home

Suppose we get to the door and John is not there, but somebody else answers: “John doesn’t live here anymore.” Now we know that that’s an invalid address.

So far, these are definitive result codes. Now it gets ambiguous, and a lot of people don’t quite understand.

MAYBE SEND TO: Who knows if someone is home?

A catch-all is an email that always responds with a valid response.

It could be invalid, or it could be valid. A lot of marketers refer to this an accept-all – but it’s really an indeterminate email. We can’t get a specific result because the server always says that it’s valid.

The catch-all is interesting because it might be a really good email to send to, but we can’t tell with absolute certainty. That’s why it doesn’t fall into one of the top two buckets.

If you’re working with a really good data provider like DiscoverOrg, those emails are almost always – like the 99th percentile – okay to send to.

DON’T SEND TO: Unknown email addresses

The last bucket of email server responses are unknowns. Unknown refers to an email that isn’t responding at that time.

If we continue our analogy of visiting a house, this would be an ambiguous response to our knock: Sometimes they answer; maybe they aren’t talking to us; maybe we’re being ignored … whatever the case might be, we cannot get an answer from that remote server.

It might be because the mailbox is full, misconfigured MX records, or other issues related to the back end of a mail server. In any case, we’re going to come back at a later time and look at those emails.

Never throw out unknown email addresses! Unknowns are important to keep, because they could be valid; we just can’t determine right now.

DON’T SEND TO: Everything else

There’s actually a fifth bucket: You may choose to remove free mail accounts, disposable addresses, and all sorts of things that could be potentially bad for an email send, depending on what your use case is.

Read it: How to Avoid the SPAM Trap

Determining bounce rate for catch-all email addresses

So, what do results look like, coming back from an email-cleaning system like Neverbounce? Accuracy differs, but let’s dive into this.

Take this example:

You send to 1,000 records:

  • 480 valid emails (48%) – Keep
  • 100 invalid emails (10%) – Delete
  • 400 catch-all emails (40%) – TBD
  • 20 unknown emails (2%) – Set aside

Catch-alls often comprise a surprisingly large group. They’re usually B2B addresses: business domains, or email addresses from the healthcare industry, government, and education-related.

At 40%, that’s a lot of email addresses! And just because those are ambiguous doesn’t necessarily mean we shouldn’t send to them.

Neverbounce has found that catch-all’s bounce at the same percentage rate as invalid emails, in most cases.

In our example, 10% of those 400 addresses will bounce when you send to them.

Making a plan to treat catch-all’s

Knowing that, you can develop a small equation: “How many of catch-all emails can I send to, while keeping the bounce rate in a high-deliverability zone?”

Most email service providers don’t allow you to send out campaigns that a bounce rate of higher than 6-8%. Try to keep your bounce rate below 3%.

Neverbounce actually guarantees that no more than 3% of your list would bounce, or we’ll refund the difference. That’s because the most critical part of deliverability is ensuring a low bounce on an ongoing basis.

Bounce might not necessarily affect the first send – but the first send could get you into hot water in the long term.

Do the math: Use your Invalid email bounce rate to calculate how many catch-all emails will bounce. Add that back in to your total.

Are you still under 3%? 4%?

What is your level of comfort, when it comes to sending? What does your email service provider allow?

Keep in mind: If 10% of your emails are bouncing, you are not delivering 90%. In fact, it is much lower. Fix that problem, and your open rates will go up, which is the metric you can see.

Again, I’m Brad from NeverBounce. If you have any other questions, reach out at any time!

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Charity Heller
About the author

Charity Heller

Content Strategist, DiscoverOrg

Charity Heller, DiscoverOrg's content strategy manager, has been developing, composing, and editing content since age 2. Before her dive into content marketing, she founded and operated a book-editing company for 10 years. Charity has a B.A. in English literature, Professional Editing Certification from U.C. Berkeley, and she's a certified Project Manager.