December 18, 2018

11 Tips to Make Sure Your Emails Avoid Spam Filters

Emails ending up in a spam folder is perhaps the worst nightmare of online marketers. The 2017 Deliverability Benchmark Reportby Validity found that 20% of all commercial emails end up as spam. The truth is, not many of us spend time going through the spam folder, looking for emails with appealing content. For that reason, it's essential that your audience sees the content you deliver in order to engage with it. To succeed in this, you'll need to avoid spam filters: here's how to do it.
1. Set Up Double Opt-In
Once new subscribers are added to your list, send them an email asking them to confirm that they actually want to hear from you. Having double opt-in helps you keep your list clean, ultimately improving your sender reputation. Whitelisting sends a clear signal to ISPs that subscribers on your list want to receive emails from you.
2. Keep Your Email List Clean
Internet Service Providers (ISPs) determine your sender reputation by monitoring bounce rates. Dormant subscribers who do not open or click your emails might also damage your domain. This means you should remove hard-bounced and dormant emails from your list. The best way to do this is to launch a Re-Engagement series. This flow will nudge inactive contacts and re-activate them, plus it will help you group your disengaged contacts and suppress them from your list.
3. Make It Easy to Unsubscribe
Having an unsubscribe link makes it easy for those who do not want to receive emails from you to opt out. What's more, it is legally required from you by the CAN-SPAM Act. It's important to know that having people unsubscribe doesn't hurt your sender reputation in any way. However, having them mark your emails as spam does way more damage. Make it easy for them to unsubscribe, so they don't have to choose the other option.
4. Don't Use Spam Trigger Words
An enticing subject line will do a lot for your email marketing, but you should be careful of the wording you use. Spamy words will cause your emails to skip recipients' inboxes and will land them in the spam folders, damaging your sender reputation. Some of the spam trigger words you should avoid are: guarantee, congratulations, winner, great offer, order now. For more information, provides a list of 455 spam trigger words to avoid.
5. Capitalization Is Not the Way to Go
Using uppercase letters in online communication is perceived as shouting and is usually considered to be rude. Emails with subject lines in uppercase look unprofessional and will most likely annoy your subscribers. This will probably result in them marking your emails as spam. Furthermore, these emails are a great way to trigger spam filters, damaging your deliverability rate. It is just too much of a risk to take. You can capitalize the first letters of words, or perhaps one word you feel should be emphasized, but that is as far as you should go.
6. Don't Include Attachments in Your Emails
Using attachments in your emails will land them in your recipients' spam folders. That's because those who send out blast emails with attachments typically tend to be spammers. Apart from this, by adding attachments to your emails, your message becomes too large, and it takes longer for it to be sent. This can cause delays in recipients receiving your emails, ultimately affecting campaign performance. But don't worry: you can still share the content that would otherwise be attached in the email by linking it in the body copy or CTA.
7. Choose a Reputable ESP
To make sure you build a good sender reputation, you should do proper research and choose a trustworthy Email Service Provider (ESP). If an ESP allows anyone to upload lists of contacts without quality control, chances are that such an ESP will attract spammers. Build a good sender reputation by choosing an ESP which has built a good reputation based on the reputation of their clients.

In case you're not satisfied with your current ESP and you want to change it, we are here to help you.
8. Authenticate Your Emails with SPF, DKIM, and DMARC
By authenticating your email, you're verifying yourself as a legitimate sender, thereby decreasing the chances of your emails going to spam. Needless to say, ISPs trust authenticated senders more and are more likely to deliver your emails into the inbox. SPF or Sender Policy Framework helps you prevent spammers from sending messages on behalf of your domain. DKIM or DomainKeys Identified Mail helps you prevent email spoofing on outgoing emails. Lastly, DMARC, or Domain-Based Message Authentication, Reporting, and Conformance, ensures that a legitimate email is properly authenticating against SPF and DKIM standards. If this is getting too complicated and you need help setting things properly, schedule a call with our email experts.
9. Use a Recognizable Sender Name
Most of us are more likely to open emails coming from known senders. An effective sender name will be consistent, making it easy for the customers to align it with your brand. Sender names with a format like firstnamelastname@domain are always a good way to go. Make sure you don't change your sender name frequently and don't use obscure sender names. Both of these would confuse your customers, making them more likely to mark your emails as spam.
10. Test Your Emails
Testing your emails is always a good option. It makes it easier for you to see what kind of customer experience you offer, and in line with that, provides you with steps to improve your email marketing program. There are several sites that allow you to test the quality of your emails by assessing how likely they are to land in spam folders.,, and will alert you if your emails are likely to trigger spam filters.
11. Email Certification and Accreditation
Lastly, you can get a sender accreditation issued by a third party. This acts as a guarantee that you are a legitimate sender. Third parties issuing certification and accreditation already have established relationships with many ISPs and spam filtering companies, allowing your emails to go past some of the spam filters all emails go through. This service is not free – but it will keep your deliverability rates high, so it's worth investing in. If you're interested, WPMU DEV provides a review of the 5 most popular SSL authorities

Spam rate doesn't have to trigger a stress response in marketers the way spam words trigger spam filters. There are steps you can take to make sure your emails land in your recipients' inboxes rather than spam folders. Applying the suggestions listed above will undoubtedly bring you closer to building a good sender reputation and sending out engaging content.

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