Email Blacklist Check: When and How to Run It

Email Blacklist Check: When and How to Run It

Email is one of the most useful communication tools we have at our disposal…

And that’s especially true if you run one of the 80% of businesses that rely on email marketing to acquire and retain customers.

But here’s the thing:

Often businesses are handicapped when it comes to taking advantage of the full power of emails because they’ve failed to maintain a good sender reputation and are on an email blacklist.

Being on an email blacklist can cripple your business’s ability to communicate with its customers and cause you to lose out on potentially thousands of dollars in profits from your email marketing.

That’s why in this article we’re going to reveal when and how to perform an email blacklist check.

What Is an Email Blacklist?

An email blacklist is a real-time list mainly used by internet service providers to identify IP addresses or domains that are known to send spam so they can block emails coming from these sources or divert them to the spam folder.

There are different kinds of blacklists like internal blacklists run by webmail providers like Gmail and Outlook and there are external blacklists run by security companies like Barracuda and Proofpoint.

If you find yourself on an email blacklist it may be due to you:

  • Receiving a large number of spam complaints from the readers you are sending to
  • Having a low-quality email list that contains spam traps
  • Having a malware infection on the system you use to send emails

Warning Signs That You May Be on an Email Blacklist

When you’re on an email blacklist there are a few “warning signs” that you should be able to easily identify:

1. Low Open Rates and Engagement

One of the first things you’ll notice if you are on an email blacklist is that your open rates have plummeted.

For example, if you had an open rate of 35% and it suddenly falls to 5% in only a short period of time that’s an easy sign that you could be on an email blacklist.

If you use an email activity checker (which lets you view your customer engagement and how responsive they are to your marketing) you may also notice that they’re not engaging.

2. High Email Bounce Rate

An email “bounce” means that your email has failed to be delivered to your recipient’s inbox.

Having a high email bounce rate is another symptom that you are on an email blacklist because it means your emails may be getting rejected.

You can tell when an email you send bounces when you receive a notification back from your mail server that it has not been delivered.

When to Perform an Email Blacklist Check

When you uncover any of the warning signs above it’s important that you run an email blacklist check as soon as possible…

And that’s even more true if you’re about to start a new email marketing campaign.

In short if you “press play” on your marketing when you’re on an email blacklist you could be throwing your money down the drain because your emails will be going straight to your customers’ spam folders (if they get delivered at all).

But marketing campaigns aren’t the only reason you send emails which is why it’s a good idea to include email blacklist checks as a regular part of your email hygiene routine.

That way whether you’re sending emails to customers, suppliers, or even friends and family you can always be confident that they’ll be read.

How to Perform an Email Blacklist Check

It’s incredibly simple to check whether you’re on an email blacklist.

One of the most common ways to do this is to check the blacklists of common blacklist providers directly on their websites.

Here’s a list of some of the most common providers of email blacklists:

  1. Spamhaus
  2. Microsoft
  3. Barracuda
  4. Proofpoint
  5. Cisco Talos

Using these sites is as simple as entering your domain name or IP address and pressing “enter”.

If your email is blacklisted you can then request to be removed from it.

Of course, searching through the blacklists owned by these sites can be time-consuming which is why we recommend that you use a dedicated email blacklist checker.

A blacklist checker is a tool that checks multiple email blacklists for you at once saving you potentially hours of work.

MXToolbox is one of these blacklist checkers that you can begin using today.

How to Avoid Being Blacklisted in the Future

There’s little point in removing yourself from an email blacklist if you’re going to be placed right back on it.

That’s why to avoid being blacklisted in the future we recommend you:

  • Build a healthy email list. You can do this by enabling double opt-in on your email list to ensure that the people who sign up to the list are real… making it easy to unsubscribe by placing a visible unsubscribe link at the bottom of every email… and using a reputable email service provider
  • Send only relevant emails. To make sure you don’t get marked as spam you can segment your audience to ensure you only send them relevant emails (the content they signed up for in the first place)
  • Comply with email marketing laws like the CAN-SPAM Act (in the US) and GDPR (in the UK)


If you fail to maintain a good email reputation and get placed on a blacklist you will not only harm your business’s ability to communicate with its customers but leave potentially thousands of dollars on the table in marketing profits.

Some warning signs that you may be on an email blacklist are:

  • Low email open rates and engagement (which you can check using an email activity checker)
  • A high email bounce rate

If you believe you may be on an email blacklist you can use a tool like MXToolbox to quickly check multiple blacklists at once.

And how can you avoid being blacklisted in the future?

By building a healthy email list, sending only relevant emails, and complying with email marketing laws.

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