Interestingly, in its recent study of customer e-mail behavior, the Email Sender and Provider Coalition found that only about 20% of recipients use the spam button in lieu of unsubscribing. Trust in the unsubscribe function is actually very high, and more than 80% use it to stop receiving e-mail they've previously requested from companies.
However, an equal number said they base their decision to hit the spam/junk button or delete the e-mail on the subject line and "From" address, and they make this decision quickly and en masse, without opening individual messages. This behavior suggests that e-mail marketers need to give special attention to both items, particularly the visibility of their brand if they have a pre-existing relationship.
If you're experiencing a high incidence of spam complaints, you should examine how engaged customers are with your brand. You'll likely find that your spam complaints as well as unsubscribe requests are coming from the customers who are least engaged—those who show no or low open and click activity. Your strategy should be to either engage these customers with content relevant to their needs or remove them from your list.
Analysis of spam complaint activity has consistently shown a direct correlation between the level of engagement and propensity to complain: the lower the engagement, the higher the risk. In e-mail marketing, the holy grail isn't the number of customers on your list; it's the number of engaged customers on your list.
Dave Lewis is an e-mail marketing consultant. He was most recently VP-market and product strategy at StrongMail Systems , a provider of e-mail delivery servers and software.