CATEGORY: Deliverability

Everything you ever wanted to know about spam traps

Everything you ever wanted to know about spam traps

Deliverability is key to a successful email marketing program. After all, subscribers can’t engage with emails they never see. But, around one in five commercial emails never reach the inbox. 

To keep email users happy, Internet Service Providers (ISPs) and email security services can’t let every email ever sent to its users slip into their inbox. Instead, they filter emails and decide to send some to spam and block others altogether.

The challenge for email marketers is that there are a large number of email providers and each one has rules and metrics which determines what they allow through and what they do not. They also ensure that their algorithms remain private to ensure that no one is able to game the system.

One thing that we do know, is that sender reputation is a critical part of the way email providers evaluate senders. Sender reputation is the score service providers assign to your IP address that indicates how likely your email is to make it into your recipient’s inbox. The higher the score the better.

There are a number of factors that affect your sender reputation including;

·         Open rates

·         Spam complaints

·         Unsubscribes

·         Opt-in rates

·         Hard bounces

But there is another factor that can play a significant part in the equation; spam traps.

What is a spam trap?

Spam traps look like real email addresses, but they are actually honeypot addresses that don’t belong to a real person and shouldn’t be used for any type of communication. A spamtrap is a honeypot used to collect spam. Spamtraps are usually e-mail addresses that are created not for communication, but rather to lure spam. These spam trap addresses are often already well-known to email providers or third-party blacklists.

There are three types of spam traps.

1.       Pristine spam traps

Pristine spam traps are email addresses that can only be acquired by black-hat methods, such as buying bot lists or scraping websites. This is the worst type of spam trap to have within your email list, as it suggests that you might be a bot, or at least that you don’t bother to keep your email list up to date.


2.       Recycled spam traps

Email providers remove email addresses from their servers that haven’t been logged into in a long time (the time range differs for each provider) for example Google is known to convert emails to spam traps after a year of inactivity. These email addresses are known as recycled spam traps. If you are still emailing an address that hasn’t been logged into in a year or more, this will be flagged by the inbox provider and will hurt your sender reputation. Put simply, it signals you aren’t updating your mailing list.


3.       Typo spam traps

If a domain name is malformed – for example – this is known as a typo spam trap. If you email this address then the message will bounce. The most common 'typo' domains are,, and One tip here is not to edit this typo and resend the email unless the person who owns it asks you to, as often people have entered the typo on purpose.

If you continually send emails to spam traps, this has a negative impact on your sender reputation and your emails are more likely to be blocked by the email inbox provider.

Keep your data clean

If you are not keeping your marketing list up to date by removing spam traps, then it’s also unlikely that you are removing users who don’t engage with you or open your emails. This shows that you’re simply spamming a list without thought.

As inbox providers want to keep these types of emails out of users’ inboxes, you’ll likely be penalized. If you email spam traps over and over again, email providers are more likely to block your emails — or at least route them into the recipient’s junk email folder.

Keeping your email list up to date is the best way to ensure that your emails don’t end up hitting spam traps. While spam traps may inevitably make it onto your list from time to time, you can minimize the impact. If you continually clean up your list by removing any email addresses as soon as the emails bounce, you can avoid adverse effects.

Use engagement to prioritise your sends

You should really only send emails to people who have engaged with your brand recently and filter out those that haven’t. This not only helps you understand who is interested and who is not and treat them accordingly, but it also allows you to weed out spam traps since those recipients will never engage with you.

For those that have not engaged with you for some time, you could try a ‘win-back’ campaign to re-engage them with your brand. If they don’t re-engage with your brand then, for the sake of your reputation, you should consider removing them from your contact list.

Engagement filtering is crucial as it ensures that you can keep your engagement rate high. This is one of the key ways to boost your sender reputation and ensure your emails land in your customers’ inboxes. Also, by giving more priority to triggered activity based emails, that send the right email to the right person at the right time are also beneficial to your sender reputation.

Read more in: When reputation is everything.

Watch our webinar

There are many technical elements to making sure your email marketing gets delivered, but the most important aspects of good deliverability relate to your data and your content. Learn about the five things you should be doing to keep your emails out of junk in our dedicated webinar.   


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