Why Marketers Should Love Spam Filters

Many marketers once thought of spam filters as potential disruptions in their subscriber relationships, but today they’re more likely to be grateful to filters for making their campaigns more effective. Here’s why.

Much like coffee is needed to flourish on a Monday (and the coffee filter ensures a grit-free cup of Joe), email needs spam filters to function correctly. Spam filters cannot be avoided. When mail is sent, it will be filtered—either to the inbox, junk folder, or completely blocked from being delivered. Understanding how spam filters work and what their purpose is will help marketers to embrace them and use them to their advantage.

What is a spam filter?
A spam filter is a program used to sort incoming mail in order to identify legitimate mail from junk, also known as spam. The original purpose of a filter was to identify spam so that mail could be blocked or placed in the spam folder. Today, mailbox providers such as Gmail use filters for additional reasoning such as deciding which folder to place mail into (i.e., Primary, Social, Promotions, Updates, and Forums).

As you can see in the two examples below, newsletters are placed in the “Updates” tab, while sale/promotions are placed in the “Promotions” tab.

Updates tab:


Promotions tab:


Why do mailbox providers use spam filters? 
As stated in Return Path’s Sender Score Benchmark Report, most email that is sent worldwide is spam. Only 28% of messages sent even make it to the inbox! The majority of email that is sent out is spam, but most of the email that is actually delivered isn’t, mainly due to filters blocking spam from consumers’ inboxes. Mailbox providers want their users to trust the email that is being delivered to them.

Benefits to the mailbox provider
Spam filtering maintains the user experience that subscribers demand, free from clearly unwanted and potentially abusive mailand that’s vital to the survival of mailbox providers. Their users represent mailbox providers’ economic lifeblood, and if their experience fails to meet expectations, they’ll disengage or even abandon their accounts altogether. Competition for new users is fierce and acquisition costs are highfar higher than the cost of retaining existing usersso mailbox providers’ investment in subscriber satisfaction, including spam filters, is economical and effective.

Benefits to the marketer
Without spam filtering, mailboxes would fill up quickly and marketers would not be able to deliver the messages that their subscribers are asking to receive. This would result in lower open rates, higher unsubscribes, and a decrease in overall revenue. Also, customers would never want to open their mailbox if, every time they did, the majority of what they saw was spam.

Benefits to the consumer
Without spam filtering, consumers would be flooded with spam. Considering the fact that the majority of all emails sent are spam, consumers would not be able to distinguish which mail they want to read and which are junk. They also wouldn’t be able to easily search for emails they need (i.e., a ticket for a flight or concert).

In order to keep inboxes clean and for people to easily find the mail they are looking for, we have to rely on spam filters. For more information about email spam filters, check out the Return Path ebook, The Ultimate Guide to Email Deliverability.

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