At some point in every email marketer's career, they will end up getting their domain or IP address blacklisted by one or more email service providers. This can be a huge interruption to your business and will impact your ability to communicate with your audience. While it happens to almost everyone at some point in time, getting your domain blacklisted can be prevented if you understand how the process works, know what practices to avoid, monitor inaction of your audiences and regularly monitor your sending reputation.
A blacklist is a database of emails and/or IP addresses that an email service provider checks against to determine if a message is spam. For email service providers, it makes a lot of sense to just check a list of known spammy addresses before parsing through the message content. At scale, this increases the efficiency of their spam detection systems.
Using blacklists isn't something email providers do to punish senders, but, rather, something they do to offer a quality experience to their user base by minimizing spam in their inbox. There are loads of lists out there and if your sending address lands on one, it can mean your emails are hitting the spam folder or not even getting delivered at all.
To get blacklisted, you'll either need to be reported for sending spam to the email provider by their users (this could be something as simple as clicking "Mark as Junk" in their email client) or sending email to a spam trap setup to catch bad mail. There are a few kinds of spam traps you should try to avoid.
Pristine Traps are email addresses that have never been used before. They are generally posted on public websites, but hidden from normal users. This way, the only people who would have them on a list would be people who scraped addresses or had other shady collection practices. If you send to a pristine trap, its telling the ESP that you are sending email to people who have not opted in to receive it and you got those emails without their consent.
Recycled Traps can get even the most honest marketers. Recycled spam traps are created from real addresses that are no longer in use or haven't been used in a long period of time. These can be email addresses from real people who opted in to your list, but they would never open or click on an email. This type of disengagement can be used by providers to identify poor list hygiene practices.
Typo Traps are spam traps setup intentionally to catch senders who send regularly to malformed, disengaged addresses. To setup typo traps, providers will catch emails going to a similar domain - "gmaik.com" for example.
Email providers are constantly developing new spam trap techniques and utilizing new abandoned addresses to identify bad practices. The best way to prevent being caught in a spam trap is to analyze each step of your sending process and ensure you are implementing best practices.
You'll notice that with all of the spam traps above, there is one thing in common: inaction. These addresses are not interacting with your content. Many marketers look at opens and clicks to determine how successful a campaign is, but neglect to think about all those users who didn't open or click. If you have a 40% open rate, then 60% of the people you emailed didn't engage at all! They didn't even see your email!
For pristine traps, those are the easiest to avoid. Just don't buy lists and don't scrape websites for email addresses. If you do find yourself in a position where you're uncertain on the origins of your list, you should take measures to sanitize your list before sending any major campaigns. Sanitizing your list can be done many ways, but, generally speaking, you can send smaller campaigns through a different domain and monitor engagement, pulling out only the most engaged users into the final list.
If you have a 40% open rate, then 60% of the people you emailed didn't engage at all! They didn't even see your email!
In the case of recycled traps, those addresses will usually hard bounce for a while before they become spam traps. So these can be avoided by automatically purging bounced addresses from your list. If an address hard bounces, there's really no reason to ever try to send to it again. If you were able to deliver an email to it, the chances of it being a recycled spam trap are high.
For typo traps, you can handle it a couple of different ways. The easiest way would be to suppress these email addresses when they hard bounce or disengage. Alternatively, you could use a list sanitation service or, if you can program, even write your own script with common typos to fix the addresses in your list.
Overall the main thing you should be focused on is identifying disengaged addresses. If you send 5 emails to someone and they don't open any of them, don't send to them again for a while. This can prevent you from throwing any red flags to their email provider and getting blacklisted from contacting other subscribers using their service.
Monitoring your reputation is one of the most important things an email marketer can do. Many, however, don't even realize this is preventing them from getting the coveted inbox-ability they strive for.
So how can you tell if you're on a blacklist? There are a number of tools online to scan your IP address or domain and see if you are blacklisted. My personal favorite is MxToolbox. MxToolbox will scan a huge list of email blacklists and let you know which ones (if any) your domain or IP addresses are listed in.
If you're on an email blacklist it can seem like a daunting task to get removed and get back to sending as usual. Generally, though, its as simple as filling out a form on the list's website requesting to be removed. If you have been blacklisted multiple times, however, it could prove much more difficult.
The blacklist operation may want you to purge certain addresses from your list, send an opt-in request to certain addresses or even change your subscriber acquisition practices to require a double opt-in strategy. Before you request to be removed from a blacklist, though, identify and fix the problems that led you to be blacklisted in the beginning. Otherwise you risk being blacklisted again, possibly permanently.
Being aware of the potential to be blacklisted without notice means marketers need to adopt practices that will inherently prevent their emails from being flagged as spam. The easiest way to prevent being blacklisted is to follow these simple rules:
Blacklists, while they can feel annoying to a marketer, are really useful when it comes to user experience. They prevent all of us from being inundated with so much spam our inboxes would become unusable. Remember, though, there is a fine line between communicating with your audience and spamming your audience. Keep your content valuable and relevant and ensure you are only sending to the segments of your audience with the greatest engagement.