Getting to the inbox should be a sender’s number one priority. After all, campaigns and emails can’t be successful if they never arrive.

Even the most experienced senders run into occasional inboxing issues. Email is constantly changing and evolving as a communication channel, which means senders must change and evolve with it. Determining how and why your emails are ending up in spam is key to taking advantage of the power of email.

Emails get sent to spam for a wide variety of reasons, with no one-size-fits-all reason or solution. Every sender’s situation is unique. From fixing misleading language to improving a poor sending reputation, we’ve compiled our list of best practices to outline how to remedy a spam problem.

CAN-SPAM compliance

First and foremost, it’s important to remember that senders have an obligation to comply with the CAN-SPAM Act. The CAN-SPAM Act, or the Controlling the Assault of Non-Solicited Pornography and Marketing Act of 2003 restricted the flow of unsolicited emails in the early 2000s and set the standard for sending commercial email. CAN-SPAM is still in effect today and dictates much of how email lands in the inbox.

Under CAN-SPAM, senders must comply with a series of rules regarding email content, including: 

      1. Do not use misleading or false information in email headers
      2. Do not use deceptive language in email subjects
      3. Clearly and conspicuously identify advertising messaging
      4. Inform recipients of your business’s location
      5. Tell recipients how to opt-out of future communications
      6. Respect opt-out requests and handle them quickly
      7. Be cognizant of what third parties or others do on your business’s behalf

Complying with these rules is, of course, a legal obligation, but they are also best practices. Sending messages that are clear, truthful, and easy to navigate can help to improve your sender reputation and your recipients’ experience.

Sender reputation

A huge part of email delivery to the inbox is your sending reputation. Your sending reputation is an indication to ISPs of how recipients respond to your messages, including how often they delete or send your messages to spam. Your sender reputation is dependent on a few metrics, including spam reports, engagement and open rates, and block rates. Learn more about checking your reputation on our blog.

Contrary to what may feel like common sense, hiding an unsubscribe link or preference center is bad for your sender reputation. By providing better access to down- and unsubscribing, recipients are less likely to delete your messages or report them as spam. Less spam reports means a better sending reputation. 

Making list-unsubscribe available or providing accessible and clear links to preference centers improves the customer experience. Sometimes, recipients just don’t want to receive your mail anymore. And that’s okay! You want engaged recipients on your list. Keeping a lean, self-cleaning list is a good thing.

List cleanliness & spam traps

Cleaning your lists may seem counterintuitive at first, but can really improve your ability to land in the inbox. Manually clean and monitor your email engagement to prevent spam traps and ensure the highest possible engagement.

Spam traps are email addresses that ISPs and other organizations use to identify and catch spammers. These addresses can read like failed deliveries or low engagement rates and tell ISPs that you’re not following email collection best practices. Regularly maintaining your email list can also help you to avoid any duplicate addresses and resolve any typos or mistakes in manually entered addresses.

Your emails may also go to spam because your recipients are receiving more mail than they anticipated or signed up for. Consider offering recipients the chance to tell you their email preferences during opt-in. Our 2019 Email Benchmark and Engagement Study found that recipients overwhelmingly prefer to give their subscription preferences at opt-in than any other time. By respecting your recipients’ preferences from the start, you’re more likely to have high engagement rates and get to the inbox rather than the spam folder. 

When it feels like you’ve done everything possible to ensure inbox delivery, the content of your messages should be next on the list for review.

Subject lines

Consider your subject lines. Remember, CAN-SPAM requires that senders use clear subject lines that do not mislead recipients. However, clear language is just a start. Subject lines are the only chance you’ll get to make several first impressions with recipients. Every message you send is a new opportunity to increase open and engagement rates and enhance your relationship with your recipients.

Effective subject lines are an art, not a science. The best email subject lines grab your attention, preview your content, and make promises that you immediately deliver upon in the message.

Generally, powerful subject lines do the following:

      • Keep it short and sweet: The shorter the subject line, the better. Brevity is important to ensuring that your subjects don’t get cut off and that recipients are drawn in.
      • Avoid clickbait: Language that sounds spammy or clickbait-y will send you to the spam folder and light up your block rates faster than anything. Remember CAN-SPAM and use clear language.
      • Use emojis sparingly: It can be tempting to use emojis in every subject line, but they can alienate some recipient groups. Use them sparingly and with purpose.
      • Get creative: Every email brings the opportunity to experiment and try new ideas. A/B test subjects to see what resonates with your audience, and segment when necessary to get the best results.

These guidelines are best practices, but there are exceptions to every rule. Experiment with new copy and language to determine what your audience responds to.

The most important thing to remember when your emails are sent to spam is to stay calm and avoid panic. Problems with spam complaints are totally fixable! With a little work and adjusting on the part of the sender, you’ll be back in the inbox in no time.

For a comprehensive guide with expert advice on getting to the inbox, check out the 2020 Email Deliverability Guide. For more email best practice tips, visit the Twilio SendGrid blog.



Brooke is a Content Marketing Associate at Twilio SendGrid contributing to the blog and writing other digital content. Brooke is a self-proclaimed pop culture geek, and when she’s not writing she can be found nerding out in Denver about her favorite TV shows and books.