Email marketing has become an integral part of most companies’ marketing programs.
Here’s an alarming statistic though: according to a recent post by Anchor Computer, in 2011, 70% of global email traffic was spam. Unfortunately for us marketers, 20% of emails marked as spam by filters were actually legitimate marketing messages.
For all of us who are following the rules and carefully crafting emails to make sure we respect those we send to, how do we avoid being wrongly blocked as spam by filters? And just what are the rules of this game anyway?
We’d love to be able to provide the cure-all to the spam filter blues, but none really exists. Spam filters have gotten super sophisticated in recent years and can flag your emails as spam for any number of reasons. On top of that, many corporate filters dutifully respond to employees marking emails as spam, learning from this and filtering similar messages going forward. So despite our best efforts as marketers, you can expect that a certain number of your messages simply won’t get through.
However, there is more at stake than simply maximizing the number of people who receive our well-intentioned emails. One mistake could actually get your email domain (the web address you use to send emails) blacklisted – and when that happens, many servers will see that you’ve been blacklisted and refuse all emails from you. It can be a bit of a process to de-blacklist your domain when that happens. (Your IT department can further advise you on this scenario and what to do about it.)
Tips to prevent the spam trap.
Take heart. There is plenty you can do to reduce the chance of being seen as a spammer. We’ve gleaned tips from a variety of online sources to provide this list of dos and don’ts.
- Keep the image-to-copy ratio as low as possible. When spam filters see a bunch of images, they think you are trying to hide spammy content since the filters can’t read the words in the graphics.
- Avoid ALL CAPS, bold, flaming red, g a p p y t e x t and exclamation points!!!!. These are the equivalent of wearing a sticker on your back that says “Kick Me.” Filters love to block emails that have this offensive stuff.
- Stick to standard fonts sizes. Using Ultra large type or tiny fine print can look spammy.
- “From” name and email address: This is not the place to get cute. Be literal and say who you are. Also, your email address should not be email@example.com. “Info” can be seen as spam. Instead, you can try something like “customercare@” or “corporate@.”
- Subject lines: keep them short, focused, free of spam words. There is a long, long list of words and phrases that can be flagged as spam. Obvious ones are “free,” “win,” “prize,” “weight loss,” “work from home,” “opportunity,” and “Dear Friend…” Having to avoid spammy words may feel highly restrictive, especially if you are actually trying to promote something like a contest. That’s where a thesaurus will come in handy. Not only do you want to get past the spam filter but the last thing you want is the actual person receiving the email to mark your email as spam without reading it because it sounds spammy.
- Body copy: minimize the use of spam words here too. For a really great list of words you should try to avoid as much as possible, visit the HubSpot Blog’s “The Ultimate List of Email SPAM Trigger Words.”
- Don’t use Microsoft Word to build your HTML email content. Use a dedicated HTML email builder that generates clean code. Microsoft Word adds lots of junk to HTML code that spam filters will flag immediately. Also, pay attention to the title and alt tags for graphics and links. The default tags generated by HTML tools are often flagged as spam.
- Don’t attach files. Ever.
- HTML links should link to real domains. Don’t link to IP addresses (like 192.168.xxx.xxx).
- Construct your emails properly. Missing MIME sections, invalid or missing message IDs, missing date and other headers are frequently flagged as spammy.
- Avoid saying “This is not spam.” That’s like saying “Trust me!” and spam filters definitely won’t. Neither will most humans.
- Be CAN-SPAM compliant. This isn’t just a good idea. It’s the law. Companies have paid stiff penalties for violating this. Click here to view the basic requirements of CAN/SPAM. And to see actual companies that have been fined for not complying, click here (provided by MailChimp).
- Use Email Authentication. Many ISPs, including the majors like AOL, Gmail, Hotmail/MSN and Yahoo!, rely on email authentication to validate that the domain you are sending emails from is trustworthy. Authentication methods include DKIM, DomainKeys, SenderID and SPF. To learn more about this, view Pardot’s excellent summary here
- Be careful about sending emails to too many people in the same company. A corporate server can easily interpret a blast to many of its employees as a spam email to a bulk emailing list.
- Ask your recipients to “white list” you in advance. If you have any kind of pre-existing relationship with your soon-to-be email recipients, kindly let them know you’d like to include them in a distribution of messages that are relevant to them and ask if they would please include your send address and from name in their list of accepted senders.
- When in doubt, get an “opt in.” It’s always better to email people who have accepted your invitation to join your email list, either directly from you or by visiting your website and filling out a form. When you get an opt-in, be sure to ask that person to remove you from his/her spam filters.
- Don’t wait too long to email to your list of opt-ins. If you wait too long, the folks who opted in to your email may forget that they did so all those months ago…and think that you are spamming them.
- Test your emails. We’ve found at least two free, online spam checkers that seem pretty comprehensive in their approach and which test using the SpamAssassin open-source spam filter approach. They are: 1) Email Spam Test and 2) IsNotSpam.
The preceding is a pretty good list of dos and don’ts, but a subject like this is always more complex. We encourage you to learn more by researching on the Internet as well as talking with your IT team, your mass emailing platform provider (such as Constant Contact or MailChimp) and your Internet Service Provider (ISP).
To help get you started, we’ve included the resources used in researching this blog post.
Here’s to the Marketing Champion in all of us. See you next time!
- MailChimp’s Resources Page »
- SendBlaster’s “Advanced hints on better email sending” »
- Striata’s “Avoid Spam Filters” »
- Pardot’s “Email Authentication” »
- Anchor Computer’s “Email Deliverability: 6 Ways to Avoid Spam Filter Blocking” »
- HubSpot’s “The Ultimate List of Email SPAM Trigger Words” »
- The CAN-SPAM Act »
- Email Spam Test »
- IsNotSpam »