All About Email Blacklisting

If your IP address goes on a blacklist, it can negatively impact your online marketing. Although blacklists are useful for minimizing spam and poor quality emails for users, if your company IP is erroneously added to one, it is definitely not good. Here is a quick look at what blacklists are and how they work, why you might be added to one, and what you can do if your IP address is blacklisted.

What are Email Blacklists?

Various organizations use email blacklists. They are real-time lists of servers and domains that have been found to send spam emails. Internet Service Providers (ISPs) and free email providers use them to ensure that unsolicited and spam content doesn’t enter their system. Both individuals and email service providers can find themselves on these blacklists, depending on the quality and quantity of emails they send, as well as the user lists they sent content to. Some ISPs will have their own internal lists, but often they use third-party lists.

Companies use them because there is such a high volume of spam content sent each day. Some sources estimate up to 85% of emails sent are spam of some sort.

How Do Email Blacklists Work?

Different lists use different criteria to determine which addresses are put on them. Some of these are technical issues. Some examples are if you’re missing or using incorrect reverse DNS information, have incorrectly configured your email server, or operate within a suspicious range of IPs. Another important factor is the past performance of your IP or server. If the inbound server has restrictions on IPs or countries, this can immediately place you on a blacklist.

The reputation of your IP also has an impact. If you send a lot of emails that often trigger spam filters in recipients, you could soon find yourself being blacklisted. You can find out if you’ve been blacklisted using a number of online checks.

Why Has My IP Been Blacklisted?

Unfortunately, even if you’ve avoided all of the mistakes we’ve mentioned above, you could still find your IP on a blacklist.

You’ve been blacklisted before.
This can happen because you have been blacklisted before and the second time around happens quicker.

You send a lot of emails to the same ISP.
If you sent out bulk mail, and too many Emails go to the same ISP, the ISP can choose to blacklist you. For instance, if you send out 50 Emails to Verizon customers within x number of minutes, the Verizon filters could blacklist you.

The recipient flags your email as spam.
In some cases, ISP’s let users submit Emails for blacklisting and it is easier for the user to hit the button to blacklist than to remove themselves from a list. In many cases, these Emails can actually be invoices, important security notices, etc., and the ISP will still block you from sending because 1 or 2 people flagged the message as spam.

How Can I Remove Myself from a Blacklist?

If you take the time, you can review blacklisting policies for the major ISP’s that are available on the Internet. Unfortunately, this is time consuming and they change constantly. Even if you take the time to keep up with the changes, you still need special software that can be configured to work around the spam filters. For instance, if you find that an ISP will blacklist any Email Address sending 20 Emails or more to their network in 5 minutes, specialized software can be set to send 19 Emails every 5 minutes. Again, this is very time consuming.

Should you find that you’ve been blacklisted, here is a small list to get the removal process started:

The best way to avoid having to deal with the time and expense of blacklist removal is to use a bulk Emailing service like Constant Contact. Most subscription bulk Emailing services will comply with standard operating procedures to avoid getting blacklisted. If they do get blacklisted, they need to deal with it rather than you. Of course there are pros and cons to bulk Emailing services, so take some time and research the various options.

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