We’ve previously discussed the difference between legitimate email marketing and spam. Unfortunately, there are a lot of disreputable (or simply ignorant) folks out there who still think that bombarding total strangers with a virtual ton of unsolicited email is a viable marketing strategy. In fact, as of March 2019, spam still accounts for more than half (56%) of all email messages sent worldwide.
What makes this particularly frustrating is how easy it is for legitimate marketers to end up on the naughty list. Even if you do everything right, you may still find your email being flagged as spam by an overzealous filter or a frustrated subscriber.
Fortunately, there are some steps you can take to avoid being summarily lumped in with all the “EARN CA$H FAST” and “YOUR A WINNER!!!!” emails.
Avoiding Spam Filters
Just a couple decades ago, spam filters were pretty primitive. Simply including the word “FREE” or too many exclamation points in your subject line would be enough to get your email banished to the junk heap. However, filters have become far more sophisticated over the past couple of decades. Now, it’s less about individual words and more about overall content.
Spam algorithms may vary from filter to filter, but the process is generally the same. The filter looks for certain criteria in an email (Does it include invalid HTML tags or hidden text? Is it talking about making a bunch of money quickly? Is it from an industry with a bad reputation?) and assigns points for infractions. If the total score reaches a predetermined threshold, then the email ends up in the junk folder.
As you might imagine, the algorithms used by most spam filters are closely-guarded secrets because they don’t want disreputable marketers figuring out how to game the system. Also, many filters are customizable, with individual administrators determining just what constitutes “spam” on their servers. So this means there are no tricks and no hard, fast rules for slipping through the spam filters. That said, here are some simple guidelines that will help you keep the accidental filtering to a minimum:
- Avoid overusing aggressively spammy phrases like “Click here!” or “Buy now!” Used judiciously, these phrases can be compelling calls to action. But when used too frequently, they stand a good chance of edging your email into spam territory.
- Go easy on the capital letters, punctuation, and special characters. Again, when used sparingly, these can be great attention getters. But when abused (“$$$ LIMITED TIME OFFER!!!!! $$$”), many filters will see it as a signal that your email is spam.
- Avoid spelling and grammar errors. Pretty basic, I know, but one of the ways spam filters differentiate between legit emails and spam is by checking for mistakes. Not only does this catch the unprofessional content of someone pretending to represent a legitimate business, but it filters out those spammers who think they can buck the system by spelling spammy words with numbers (“CH34P PR3$CR1PT10N$!!!”).
- Keep your code clean. Emails are sent in HTML. Most email applications like Outlook or Gmail hide this code when you compose emails, but it’s still there. Using a dedicated email marketing application can minimize extra code, but it can still be pulled in if you copy and paste from Microsoft Word or Google Docs. Sloppy code and extra tags can trigger spam filters, so always copy and paste your text from a text editor like Notepad++ or BBEdit.
- Don’t send messages that consist only of one big image. Spam filters can’t read images, so many will err on the side of caution and assume you’re trying to bypass them.
- Do periodic blacklist checks. Free services like What Is My IP Address allow you to enter your IP address to see if it has been listed on an anti-spam database. Because databases share information, if you’re listed on one, you’re likely listed on several.
- Ask your subscribers to add you to their list of approved senders. Even if something in your email accidentally triggers the spam filter, you’ll still get through if you’re on your recipients’ white list.
Dodging the Dreaded “Block Sender” Button
In addition to automated spam filters, email marketers also have to contend with recipients who manually flag their messages as spam. A few isolated instances are nothing to worry about, but widespread behavior of this kind will quickly damage your email sender reputation.
The best way to minimize this problem is to avoid sending out unsolicited emails in the first place. A legitimate email marketing campaign should be one in which the recipients have opted in and added themselves to your mailing list. Do not ever buy or rent email lists. It may be legal, but it’s a horrible marketing strategy. The vast majority of folks on a purchased list will have no interest in your message.
Most will ignore you, but many will mark you as spam.
You should also take the time to familiarize yourself with the requirements of the CAN-SPAM Act, which regulates commercial email messages in the U.S. CAN-SPAM makes it illegal to use deceptive or misleading language in your marketing messages, and requires you to provide a clear (and functional) opt-out process for recipients who no longer want to receive your emails.
Even with a bona fide subscriber list and CAN-SPAM-compliant content, your emails may still get flagged by absent-minded recipients who forget they signed up, or by disinterested readers who would rather not go through the trouble of unsubscribing. You can mitigate this kind of behavior by taking the following steps:
- Occasionally purge your mailing list of inactive subscribers (those who have not opened or clicked your emails). Not only will this help you increase your engagement rates, it’ll rid you of the recipients most likely to flag you. If you’re reluctant to write these folks off, you can always ask them for feedback in an attempt to re-engage them.
- Don’t oversend to your subscribers. Even your biggest fans may rethink their decision to subscribe if you bury them in a deluge of emails.
- Don’t undersend to your subscribers. Permission tends to go stale within half a year or so. If your subscribers haven’t heard from you over the past six months, they may forget they opted in to your email list in the first place.
- Make sure you’re sending your recipients something of value. If all you’re doing is bombarding them with sales pitches, they’re going to tire of your emails rather quickly. Email marketing should be about building relationships with your customers, not simply moving product or hawking services.
Editors note: This article was originally published in November 2018 and is periodically updated for the most current and accurate information on email spam filters.