How Do I Clean My Email List?

Avatar for Fernanda Moura Fernanda Moura
Avatar for Fernanda Moura Fernanda Moura

March 30, 2023

4 min read

How Do I Clean My Email List?

ny business, regardless of its size, has email lists that they are not sure if they are valid or not. And today, we’re going to show you step-by-step how to clean your list with Emailable.

Lists decay over time and, as marketers, we need to be able to distinguish between valid and invalid emails before sending out email marketing campaigns. And Emailable exists to make this work much easier for you. Emailable is a very accurate email verification tool, offering multiple solutions for verification such as bulk, native integrations, and API solutions for both large amounts of emails and real-time browser-side verifications. Today we’re going to show how easy it is to bulk verify your list with Emailable.

Why does your list need cleaning?

Email lists decay on average by 2% every month, which means that over 20% of the emails on your list become undeliverable every year. And this is, unfortunately, inevitable and it’s not your fault. An email becomes invalid for several reasons, when people stop using old email addresses, replace them with newer ones, if they change companies or roles inside the same company, and no longer use this address, or if unqualified leads opt out of emails. Although growing your list and sending to more contacts can be enticing, it can actually do harm to your sender’s reputation if the recipients are not engaging with your emails, or even marking them as “spam”. That’s why it is recommendable that you focus on collecting opt-in leads as they will help improve your sender reputation and get you out of the spam folder.

If you’ve read our posts, you already know that verifying your email list can significantly improve your email marketing campaign and even increase your revenue by reducing email bounce rates and improving your email deliverability.

How to get started?

List cleaning is very simple, you can improve your email deliverability with an easy bulk upload solution.

First, choose your list source. You can upload your list from a computer or import it directly from your email marketing platform to start your list verification.

After uploading your lists, you can then verify them. At this point, your lists are going to be verified in real-time and will only take a few minutes depending on the size of the list. Now you can analyze your list and see your results. You can see how your list turns out, you will receive a detailed report with emails organized by status: deliverable, undeliverable, risky, unknown, or duplicate

You can then export a fully customizable list, you can then export your most clean list to send your emails with confidence and see an increase in your ROI, and open rates.

Which results to export?

Verifying a list of emails will return results on the email addresses, each email address is given a state that represents the overall quality and deliverability of the email. The states are determined by its score. Each email verified is given an email quality score, ranking its deliverability on a scale from 0 - 100.
The numbers also correspond with a deliverability category:
  • 0 = Undeliverable
  • 1 - 79 = Risky
  • 80 - 100 = Deliverable

5 states can result from the verification process. Let’s talk about these states and breakdown the possible reasons for these results.


Deliverable emails are those that Emailable can determine with a high level of confidence that the email address is associated with a valid account.


The undeliverable result will return when Emailable can determine with a high level of confidence that the email address is not associated with a valid account. Here are possible reasons for Undeliverable emails:

  • Invalid Email: The email address does not pass syntax validations.
  • Invalid Domain: The email address domain does not exist, is not valid, or should not be mailed to.
  • Rejected Email: The email address was rejected by the mail server because it does not exist.
  • Invalid SMTP: The mail server returned an unexpected or invalid response.


Risky emails are those that seem to be deliverable but should be used with caution due to low quality or deliverability.
Possible reasons for Risky emails:

  • Low Quality: The email address has quality issues that may make it a risky or low-value address.
  • Low Deliverability: The email address appears to be deliverable, but deliverability cannot be guaranteed.
  • Deciding whether or not to send to risky or deliverable addresses depends on how much chance you want to take with bounce and your sender’s reputation. If you’re looking to maintain a 99% deliverability rate, it’s highly recommended to send only to the “deliverable” emails on your list. Emailable offers a 99% deliverability guarantee so you can be confident that the results you receive for “deliverable” emails are very accurate.


When the domain associated with the email address is not responding, the response Unknown will be returned. It means that it wasn’t possible to determine the validity of the email account. Some possible reasons for Unknown emails are:

  • No Connect: Could not connect to the mail server.
  • Timeout: Mail server session or DNS query timed out.
  • Unavailable SMTP: The mail server was unavailable to process our request at this time.
  • Unexpected Error: An unexpected error occurred.

Unknown scores are not charged for, so you can re-attempt these verifications at a later time, as you’ll not be charged for those. Usually, waiting just a few minutes will be sufficient to return a score for these.


When the list contains more than one of the same emails, they’re automatically deleted from the export. Emailable doesn’t charge for duplicates on the same list and Unknown results.

Wrapping it up

You now have a clean list with your new results! See how your lists continue to improve as you habitually clean them. You need to be cleaning your lists regularly to maintain your good sender reputation score, decrease bounce rates, and improve overall ROI.

Industry experts suggest that you clean your email lists every 3-4 months to maintain a healthy list and help ensure that you stay out of spam traps and off of any blacklists. When you are actually sending to people that are interested and engaging with your content, this helps increase your sales overall.

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