Home » What is blacklist email check and why you should incorporate it
What is blacklist email check and why you should incorporate it

What is blacklist email check and why you should incorporate it

The blacklist email check should be part of every email marketer’s planning. That’s because your IP or domain could be blacklisted without you even knowing it!

And the next thing you know, delivery rates plummet, the number of bounced emails increases and a host of other damages hit your investments.

It is recommended that you carry out a blacklist email check on a regular basis. This way, you can monitor the health of your email marketing and detect potential problems early on.

But before you put this into practice, let’s understand why you can end up on a blacklist without even knowing it.

Why can you be blacklisted even if you do everything right?

It all starts with the blocking of the providers. Each provider has its own blacklist with different criteria. However, they all have elements in common. Let’s see what they are:

  • Unsubscribe button: users may be annoyed if your unsubscribe button is not in a clear position on the email layout, forcing them to do a real search to find it.

It’s important to remember that the “unsubscribe” button signals the lead’s lack of interest in continuing to receive your emails. If they opt out and continue to receive messages, the level of irritation can increase.

And irritated users click on “Report Spam”; a much worse button than unsubscribe. So respect your lead’s decisions, as many spam complaints lead to blacklists.

  • Volume of emails: another reason that leads distracted senders to blacklists is the high volume of emails sent. Anyone who works with email marketing knows that sends must be scalable.

In other words, if your lists contain free providers, start small and gradually increase the number of emails sent, so that the provider understands that your list has not been bought, but has been built up gradually, as it should be.

Suddenly sending too many emails indicates that you haven’t created your own list, but have bought one from a commercial source. And it’s worth remembering that purchased lists suffer harsh penalties, such as inclusion on public and private blacklists.

  • Bounces: these are emails that fail to be delivered for temporary reasons (which can be corrected over time) or permanent reasons (spamtraps, for example).

Bases containing at least 3% bounces are immediately blocked. So keep an eye on the quality of your lists by checking your emails frequently. Open your account now and stay away from blacklists!

Types of blacklists

Take a look at the three types of blacklist and keep your email marketing away from them:

  • Blacklists from email providers: we’ve just talked about them. They are the blocks that email marketing suffers from that provider (Gmail, Yahoo etc.). For example: a mailing list full of bounces has the sending IP or domain blocked. And if this recurs, the provider can not only keep the sender blocked on its own blacklist, but also send them to public or private blacklists.
  • Public blacklists: these are lists that notify the market which addresses are spammers. In other words, IPs or domains that are part of this group cannot be trusted. Public blacklists are constantly consulted by email providers and private blacklists record the information in their anti-spam filters.
  • Private blacklists: these are companies or web services that set up their own anti-spam filters to block addresses suspected of spreading spam. They are more common in banks, large companies, government services and other agents that need a more robust data protection and security system.

In short, blacklisting is a very serious matter and represents a huge loss in investment because, once listed, the sender’s email communication is literally cut off. Not to mention the fact that you won’t be able to approach new leads.

How to do a blacklist email check

Checking whether your IP or domain is on a blacklist is nothing more than paying attention to whether spam complaints have increased and, above all, knowing why.

In other words, it means not being caught by surprise, as we can see in the previous paragraph. But as well as keeping an eye on your user’s behavior and your campaigns, you need to consult some blacklisting platforms.

BlacklistAlert, MultiRBL and MXToolBox are some of the most popular and efficient free consultation platforms on the market.

Email validation is the safest way to do blacklist email check automatically, since suspicious addresses are not part of the lists that go through the check.

This way, you don’t run the risk of being blocked by ISPs and subsequently included on a public or private blacklist because of invalid emails.

Find out what impact invalid emails have on your email marketing results by watching our webinar!

Rodrigo Gonçalves, COO of SafetyMails and an authority on the subject, analyzes the topic and answers all your questions!

Blacklist email check: conclusion

To stay away from blacklists, follow good email marketing practices:

  • Build a healthy mailing list by asking users for their permission (Opt-In).
  • Keep the unsubscribe button accessible and, if this happens, find out why.
  • Watch the subject line of your emails: make sure the words are not suspicious, such as “last chance”, for example.
  • Follow the image size standards required by ISPs (500Kb should be the maximum).
  • Never buy or exchange mailing lists.
  • Check your databases frequently.


Why should email marketers do a blacklist email check?

Blacklist checking means being attentive to the behavior of email campaigns as well as users. High unsubscribe rates signal dissatisfaction, for example. When the professional is vigilant, the problem is detected early on and blacklisting can be avoided. Not to mention the huge losses that can also be prevented.

What causes an IP or domain to be classified as a spammer?

Bounces, spam complaints, high sending volumes, purchased bases, spamtraps, lists containing disposable emails and other factors can classify an email marketing sender as a spammer.

What are the types of blacklist?

Provider blacklists, which are blocks; public blacklists, which notify which IPs and domains are spammers; and private blacklists, which are more common in large companies, banks and services that need a more robust data protection system.

How do I know if my IP or domain is blacklisted?

In addition to observing the behavior of email marketing through the drop in delivery rate, the professional can consult blacklist disclosure platforms such as BlacklistAlert, MultiRBL, and MXToolBox.