Six Steps to Avoid Spam Filters

In the war against spam, don’t let your legitimate permission-based email become collateral damage. 

You’ve worked hard to build your email list the right way, making sure every recipient has opted in and given permission to receive your email. So why, if you’ve done everything right, is your email getting filtered to the spam folder?

Legitimate email gets spam filtered if there’s something about the message -- or recipients’ reactions to it -- that make it look like spam. 

These six steps will help ensure your permission-based email gets in the inbox, and not the spam folder:

1. Send email people want to receive. The biggest reason email gets filtered is because recipients report the message as spam. If there are too many complaints, the email gets filtered. 

Why do people complain about email they requested? Perhaps they opted in ages ago, and forgot. The email may not be what they expected, or may come too frequently. Maybe they never really asked for it to begin with -- they neglected to uncheck a box during checkout, say, or they opted in to receive “finance news” on an affiliate website, without reading the privacy policy’s fine print.

Whatever the reason, as mentioned above, if too many recipients hit the “spam” button for your message, your mail will be filtered. So, before sending an email message to your permission-based list, consider carefully if it’s this kind of message your recipients gave you permission to send.

2. Send more slowly. If you’ve got a large list, a hot special or breaking news, the last thing you’ll want to do is to slow the sending speed. But when ISPs detect a flood of email, it looks like the work of a virus or a spammer. They may accept the mail, but relegate it to the spam folder, or accept it so slowly that it compromises your sending speeds to all your recipients (that’s called tarpitting). They may simply reject your mail outright.

To combat these send limitations, either slow down your mailing speed in general, or slow it down for the particular domains that are using send limitations to combat spam. You may not be able to send quickly, but at least your message will get there.

3. Get whitelisted. The opposite of a blacklist, or a list of known spammers, a whitelist is a list of “good” senders. AOL’s whitelist is the best known, but other ISPs have whitelists as well. To get on a whitelist, write to postmaster@thedomainyou’, explain your opt-in process, and request to be put on the whitelist, if one exists. Keep in mind that being whitelisted isn’t a license to spam, but rather a relationship where if you follow certain policies, the ISP agrees to not filter or block your email without notifying you first.

Individual recipients may be able to maintain a whitelist, too, so ask them to add your email address to their address book, whitelist or permitted sender list.

4. Look legitimate. Make sure you have the right DNS entries for your domain, and that you have SPF and Sender ID records as well. 

DNS (for Domain Name Service) identifies the IP address(es) (e.g., assigned to a domain name (e.g., ISPs receiving your mail may check your DNS record to ensure that it’s configured properly and that you’re not listed in any of the hundreds of blacklists individuals and organizations maintain of senders they believe are spammers.

You may add additional SPF (Sender Permitted Framework) and Sender ID information to your DNS record so others can identify which addresses on the internet are authorized to send mail for your domain.

Few ISPs seem to be blocking mail without SPF and Sender ID outright, but it can be a factor in whether or not a message is spam filtered. MSN/Hotmail has started labeling mail that does not have a Sender ID record with the fabled Yellow Box of Doom:

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Thus far, Sender ID doesn’t by itself relegate a message to the Junk folder, but in the future it might. Make sure your DNS record has this additional information, and you remove one reason to filter or block your mail.

5. Send the message addressed To: the recipient. Nobody likes getting mail addressed to somebody else, and some ISPs will automatically filter mail that does not have the recipient’s email address in its To: field. Some email marketing programs use the CC or BCC to send the same message to multiple recipients. That’s fine when you’re sending the same message to five friends, but not to 500 or 500,000. Use a quality email marketing program that can send individual email messages personalized with the recipient’s email address in the To: field.

6. Don’t try to “trick” spam filters. The spammers are way ahead of you when it comes to creative copy, and the spam filters are only a step or two behind. If a word is inherently spammy, it’s even more so when the sender tries to disguise it with numbers, misspellings or spaces (exclamation points don’t help, either). 

That said, the spammiest content can go to the inbox if no one complains (or if the ISP doesn’t receive a lot of it), and the “cleanest” content can get filtered immediately if it’s received by people who don’t want it.

Although these steps will help your email get delivered, there’s no single solution that can guarantee it. As spammers change their tactics to sidestep spam filters, ISPs need to change how they monitor email so they can keep their customers’ inboxes clean. The result? The very same message may sail to the inbox one week, but be filtered or blocked outright the next.  

On the other hand, these steps can often completely resolve deliverability problems. Try these steps first to improve deliverability before taking the next one: contacting the ISP directly.

Wendy Roth is the training manager for Lyris Technologies, a pioneer in email marketing solutions since 1994. She works closely with enterprise-level marketing and advertising professionals to help them achieve their email-related objectives, and collaborates with engineering teams to ensure Lyris' products continue to be based on marketers' changing needs.