Viagra & Nigerian Princes: 5 Steps to Spam-Proof Your Email
Spam filters are our inbox guard dogs, and unless you are truly intrigued by the promise of all things far too good to be true, you’re probably glad they exist. But unfortunately for marketers, many perfectly innocent email campaigns get snagged in spam filters’ jaws. According to MailChimp, even the cleanest campaigns can expect to get 1-2 spam abuse reports per 50,000 recipients. That’s why we took a closer look at the prevalence of spammy terms in our recent Email Data Report for tips on how to spam-proof your email campaigns.
In the sample of nearly 100,000 emails we analyzed for “spamminess,” the results were good: we found spammy terms “reminder,” “percent off,” and “help” in less than 1% of emails, collectively.
While these numbers may sound low and inconsequential, email marketers have to be attentive to even sporadic spam abuse complaints to avoid delivery disruptions. Internet service providers (ISPs) are hyper-vigilant about monitoring spam abuse, and can choose to not deliver or even block your messages entirely if you’re marked as a repeat offender. To avoid being blacklisted, marketers must be proactive about monitoring complaints per campaign and understand the nuances of their ISPs’ spam thresholds.
Know Thy Enemy
While spam filters used to operate with a “one strike and you’re out” approach, email marketers should be thankful that more elegant spam assessments have developed over time. SpamAssassin is one such example of a popular and highly-evolved spam filter.
SpamAssassin is an open-sourced software released under the Apache License 2.0 that uses content-matching rules to filter email spam. If you picture an assembly line with emails coming down a conveyor belt, SpamAssassin is the lever that sends emails straight to the junk pile. But rather than just trashing the offending emails, SpanAssassin collects and studies the junk pile and shares the spammy intel it acquires so that it can filter smarter in the future.
SpanAssassin is designed based around heuristics, or trial and error pattern recognition, so that it can adapt to typical email behaviors. Every email that passes through its filter is tested according to a spam rulebook that analyzes the subject, text, and HTML code of the email — in addition to cross-checking its IP address and domain name — all to determine whether the email is inbox-appropriate or not. The score of each mini-test accumulates into a final SpamAssassin score that serves as a testament to each email’s spamminess.
Each mini-test is weighted from full points to fractions of a point, and an email can even receive negative points in a category. The higher the final SpamAssassin score, the more spammy the email, so negative scores are especially good on the SpamAssassin scale. Each ISP has different spam thresholds, but ideally email marketers should shoot for a SpamAssassin score of 5 or lower to ensure deliverability.
What does this mean for marketers?
If your email ends up in the spam folder, that’s a lot of hard work gone to waste. So keep a close eye on your email open rates and bounce rates — any abnormally low numbers could be signs that your message was labeled as spam. Many established ESPs (such as MailChimp) can recover feedback from various ISPs, store spam alerts, and automatically unsubscribe recipients that report an email as spam, all of which are powerful tools for email marketers. Still, “spammy” terms aren’t a finite list, but are constantly evolving in response to our cultural lexicon; there was once a time when Angelina Jolie was the ultimate email bait name-dropped by spammers in the hopes that you’d be tempted to click and see what’s inside.
To help you navigate the ever-evolving spammiverse, here are a few simple best practices that can help keep your email campaigns in the clear:
1. Avoid spammy terms.
Common offenders include: percent off, reminder, help, affordable, prizes, win, free, risk-free, urgent, and all-new. Take a look at HubSpot’s Ultimate List of email SPAM Trigger Words for more offenders, broken down by category.
2. Check for HTML coding errors.
Spam filters are sensitive to poorly coded emails, since coding errors are typical in emails designed in Word.
3. Use a clear and recognizable “from” name.
If a recipient can’t recognize where your email is coming from, they’re that much more likely to unsubscribe or mark it as spam.
4. Don’t hide your “Unsubscribe” link.
Some people just don’t like marketing emails, and that’s okay. Do your recipients the courtesy of making it quick and easy to opt out of your email list. Otherwise, they might resort to reporting your email as spam, and nobody wants that.
5. Use double opt-in.
The double opt-in has become standard for all of the more popular and reputable email marketing managers (like MailChimp). The two-step process ensures that every recipient added to your email list gave permission for you to do so, and reduces the odds of a spam abuse report for recipients who are accidentally or fraudulently subscribed.
Incorporating these steps as part of your email marketing due diligence will help to keep your SpamAssassin scores down and your messages out of spam filters’ fetters so you can focus on what’s important: engaging with your audience. Oh, and you should probably avoid any mention of wealthy Nigerian princes too — spam filters can typically tell if an email is too good to be true (even if many average email users can’t).
Kara Burney is the Content Marketing Maven at TrackMaven, the Competitive Intelligence platform for Digital Marketers. Have content marketing questions or topics you'd like covered on the TrackMaven blog? Tweet her your ideas! See more of Kara's posts
