Read Time: 6 min

Experts Share: Why Emails Go to Spam Instead of the Inbox

Email marketing doesn’t end once an email has been written, designed, developed, tested—or even sent. In fact, all that hard work is for nothing if an email never makes its way to the intended recipient. But the reason behind why emails go to spam instead of the inbox is far more complicated than it seems.

Read on to find out which factors experts from Litmus, Salesforce, Yahoo, and SocketLabs say you should pay attention to make sure your emails stand the best chance of making it to the inbox.

(To catch all of their lively conversation, access the full webinar on-demand here.)

Confirm your authentication and infrastructure

Authenticate any domain that you use with your Sender Policy Framework (SPF) record, DomainKeys Identified Mail (DKIM), and Domain-based Message Authentication, Reporting & Conformance (DMARC).

Dimiter Batmazian, Solution Architect, Deliverability Services at Salesforce Marketing Cloud says these are the most basic steps to ensuring your mail can be delivered without issues.

Collect permissions before you send

Confirm that subscribers you intend to mail are opted-in and that you’ve got the right permissions in place. Double check:

  • Have you established how often subscribers want to receive your messages?
  • Do you know what kind of content they want to receive?

“The quickest way to tank your inbox placement is to generate a lot of complaints by sending to people who didn’t expect to hear from you,” says Lauren Meyer, Chief Marketing Officer at SocketLabs.

Avoid massive spikes in send volume

Each mailbox provider has a different algorithm that drives deliverability decisions, but they all aim to make sure each message is safe. “Our goal is to protect users and our system from the 90% of connections that are malicious that we don’t accept,” says Lili Crowley, Lead Postmaster at Yahoo.

She explains that spikes in volume can play a major role in whether messages make it to the inbox. If you triple the volume you typically send, the email provider could think you’ve been compromised. If you know you’ll have a major spike in volume for some reason, communicate with the email provider in advance.

Make sure your content is true and relevant

You’ve probably heard certain words in a subject line will land you in the spam folder. Meyer says it’s actually not the words themselves. It’s the way they’re used and the reaction they elicit from your subscriber.

Is what you’re offering really free? Is your flash sale really a rare opportunity (or are you spinning the same promotion you offer each week)?

When you use these terms correctly, they’re not necessarily going to land your email in the spam folder. But when they’re used incorrectly and/or are misleading, they can generate both spam complaints and list churn.

Whether your email lands in the inbox or spam is far more complex than a word in a subject line.

Pay close attention to your data signals

Spam filters operate in many layers. And because they lean on machine learning and artificial intelligence (AI) that adjusts in real time, the “rules” are constantly changing.

Instead of trying to game your way into the inbox, pay attention to the definitive data that indicates what’s really going on in your email program. Watch for trends in email metrics like unsubscribes, engagement, and complaint rates so you know what’s working (and not) before you’re faced with an issue.

Cater content to customers

Be prepared to tweak your program based on trends you’re seeing. If you see an uptick in spam complaints, that’s a signal worth paying attention to—and it can mean any number of things.

Perhaps you’ve made it too difficult to unsubscribe. Maybe you haven’t confirmed the type of message or message frequency different segments of your audience want. Try different approaches when you notice a rise in negative signals, and/or a fall off in engagement.

“It goes back to observing those best practices, and looking at the data,” says Batmazian. “We don’t usually see changes overnight. Something causes it to happen. The sooner you act on those triggers, the sooner you can address them.”

How can you get out of the spam folder and back in the inbox?

If you do find yourself in the spam folder, Batmazian recommends starting from the ground up to identify the issue.

  • Does everything check out with your infrastructure and authentication?
  • Is your segmentation correct? (Are there people on your list you should have suppressed?)
  • Could the content or timelines of your message be improved?
  • Is there something you could/should change about your audience?
  • Did your IP and domain reputation drop? Look into the metrics and to identify what caused it.

Once you’ve taken those steps, go back in time. “Day-to-day metrics might not be meaningful—but week over week complaints would be,” says Crowley. “If you are running a good email program—blips can happen. If you have a persistent issue, there’s probably a reason.”

Practice patience

As you try to make your way back into the inbox, dial back who you are mailing. Focus on your subscribers who are the most engaged––and prepare to be patient.

“At Litmus, we had an issue with getting delivered in the spam folder in Gmail a few years ago, says Jaina Mistry, Senior Email Marketing Manager at Litmus. “We dialed back to our most engaged audience. It took us about eight to 12 weeks to finally get all of our emails back in the inbox. But that’s what we did—and it did work.”


Make it to the inbox—not the junk folder

70% of emails show at least one spam-related issue that could keep them from reaching the inbox. Litmus Spam Testing scans your emails against 25+ different tests, identifies any issues, and provides actionable advice on how to fix them.

Learn how


Stephanie Christensen

Stephanie Christensen

Stephanie Christensen was the Director, Content Marketing at Litmus