Email Marketing Best Practices: How To Stay Out Of The Spam Folder

Heidi Haskell on Email Marketing

Wouldn’t it be nice to have a list of rules to follow that would guarantee that our emails never ended up in the spam folder?

Of course there are regulations we all have to follow for commercial emails (per the CAN-SPAM Act), but aside from following these regulations, it’s really the recipient interaction with your emails that has more of an impact on you reaching the inbox than the content itself.

If someone wants to see your email and interacts with it, it will absolutely end up in the inbox, regardless of what the email actually says. Everybody has control over what they see in their inbox, which gives us marketers frustratingly little control over which folder we land in.

What we can control is the likelihood of ending up in the inbox.

Though there are no guarantees, there are a few things we can do to increase our chances.

Give Them The Email They Want

First and foremost, increase your chances of ending up in the inbox by producing the email content your audience wants to see and interact with.

It is a major goal for email service providers (ESPs) to make sure that users are not getting bombarded with unwanted email, so don’t be unwanted.

When an ESP notices that a good amount of recipients are opening and clicking on your emails, it’s very likely that your emails will not get trapped in spam for the other recipients since your content appears to be trustworthy.

This is why having recipients add you to their address books, and/or participate in double opt-in is especially important.

The Power of Address Books and Double Opt-In

A recipient server cannot tell whether or not your address has been added to someone’s address book, or if an email was double opt in. But if a good portion of those who received an email from you interact with it in some way, the service provider assumes that the mail is desired and important.

So it sends your future emails on their merry way to inbox land.

Double opt-in also helps you to keep your list full of only active email addresses.

Remember, ESP’s also have ESP (Extra Sensory Perception). They just have “ways of knowing” and punishing you if you are buying lists or continuing to send to inactive email addresses.

Stay Away From Spam Triggers

Unfortunately there is no magical word list to avoid in your emails to prevent them from going to the spam folder. Every email service provider has different regulations and standards.

Certain words do have the ability to trigger a spam filter, but this doesn’t happen every time.

The main reason triggers aren’t consistent is that if users are openly engaging with content that happens to contain trigger words, the ESP has no reason to send it to spam. If people want to open and click on emails that are full of dollar signs and “FREE!!!” then that’s their business, not the ESP’s.

But since we are all aiming to increase our chances of ending up in the inbox it can help to stay away from the words which have a documented tendency to trigger a spam allocation. This includes such words as:

save, free, sell, buy, deal, discount, offer, make money, work from home, and basically anything related to selling/anything sexually related.

It can also be helpful to avoid using excessive punctuation marks or symbols:


Since items like these are often found in email ads, if you use them in your emails and your engagement rate is low, ESP’s might be tempted to flush you down the spam drain.

Check Your IP Before You Wreck Your IP

Now for some technical talk: your domain/IP reputation is extremely important to an Email Service Provider.

If you’ve sent email in the past that has had a high bounce rate, or if you have a history of being reported as spam, you may have trouble delivering mail to the inbox going forward until that reputation is improved.

Keep in mind that each ESP has different standards, and so Gmail may have a completely different opinion of your sending reputation than Yahoo does, for example.

Just as it is with actors trying to get auditions for the next Star Wars movie, your personal reputation is everything when it comes to getting in the email inbox door.

This means that you’ll want to protect your reputation at all costs by keeping your lists clean and sending emails that people actually want to read.

No matter the potential payoff, don’t gamble your sending reputation on a potentially sketchy email campaign.

IP Whitelabeling With 3rd Party Senders

Just a little bit more technical insight here; hang on — it’s very important!

If you use a third- party sender, like SendGrid or Mandrill, it can be extremely beneficial to use IP whitelabeling.

IP Whitelabeling can prevent any credibility issues because it makes the email appear to the ESP as though the email is coming directly from you (even though you used a third party sender).

Using domain white labeling in conjunction with IP whitelabeling can significantly increase your deliverability rate. This also makes recipients more likely to want to open your message since they’ll recognize the source.

They subscribed to updates from you, after all, not from Mandrill or Sendgrid.

Basically when everything looks like it’s coming directly from you, your emails are more likely to be trusted by everyone.

Recipient Email Service Providers can track when your mail is being sent through a third party without white labeling, and this can throw up red flags.

To the ESP, it takes a bit away from your credibility when you are depending on the reputation of a third party to send your email, instead of your own reputation. But remember, if your IP reputation goes south, so do your chances of getting in the inbox.

Striving For Useful Email

Email marketing really is a dance of knowing and avoiding the spam danger zones and consistently tweaking your content to make sure it’s engaging and useful to your target market.

Email Service Providers are just asking that we provide authentic and meaningful content to its recipients.

Even if that weren’t the case, shouldn’t that be what we should strive for anyway?

For more email tips on the technical side, you can check out 10 Tips To Keep Out Of The Spam Folder.