Internet Service Providers use spam-blocking measures to sort through incoming mail and filter out messages that are identified as unwanted or as spam. Sometimes, however, these measures block legitimate emails. If you're worried that your emails are being marked as spam, you can run a spam check to narrow down why your email is being blocked. While all spam filters are different, there are some best practices you can follow to minimize the possibility that your emails will be filtered out as spam.
In both the subject line and body of an email, there are certain words, phrases, and characters that can cause it to be sent to the spam folder. One instance may not be enough to cause the email to be filtered, but the more you have throughout your campaign, the greater the chances:
Emails that use too many images, or are all one image, could trigger a spam filter. Using several lines of text to offset the images can help prevent this. Additionally, some filters are sophisticated enough to detect an image’s content, so it’s best to avoid any photos with explicit content.
It's common for spammers to make it look like you're clicking on a link for one thing, but it's actually a link to something else, and spam filters look for this. Even something innocent, like a text link that says "Please visit our website at www.mikeslandscaping.com", but the URL portion is linked to "www.mikeslandscaping.com/home", can be seen as spam.
Constant Contact emails are enabled with link tracking for your click reports, which changes them slightly. It's best to avoid using the URL as the link text because it will never match the URL behind it and has a high likelihood of triggering a spam filter.
Content isn’t the only cause of emails being filtered as spam. Your reputation as an email sender, along with your contacts' engagement with your emails, can affect it. If your emails consistently have poor engagement, such as low opens or high bounces, filters may adapt to that and start delivering your email to the spam folder. Be sure to optimize your subject lines to help improve deliverability and open rates, and send relevant information to your contacts to improve engagement.
No matter how great your engagement is, however, if you’re consistently generating spam complaints or find that your domain is on a blocklist, you may start to see your emails get filtered as spam. Any email marketing you may have done before using Constant Contact could have affected your email sender reputation, especially if you weren’t able to track things like bounces and spam complaints. Make sure you're following these best practices to reduce spam reports and improve your sender reputation.
In general, sending from a free email address (Gmail, Yahoo, AOL, etc.) can cause an email to be delivered to the spam folder, depending on the domain’s DMARC policy. Although this is rarely an issue when sending through Constant Contact (we've taken measures to help prevent this), sending from your own domain is still considered a best practice and is the best way to prevent bounces caused by free email services. When sending from your own domain, be sure to self-authenticate your emails to help ISPs identify your email as legitimate and build your reputation as a safe sender.
If your contacts are telling you that they're not receiving your email, ask them to safelist your email address in their email account or security program. Safelisting (formerly referred to as "whitelisting") an email address ensures that emails sent from that specific address reach the Inbox, instead of being marked as spam.
Avoid copying a sent email and sending it again to the same contact list with unchanged content and the same subject line as the first email. This can result in spam triggers. If you do resend an email to a contact list—if you're sending a reminder email, for example—make sure to edit the subject line.
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