Based on our observations with our customers, seeing an IP address on a spam list is quite common for AWS users. Here are some reasons why this happens:
Shared IP Pool: By default, AWS sends emails from a shared IP pool unless a dedicated IP is used. These IP addresses were previously used by other AWS users, and their activities may have caused the IP to be listed on spam lists. When this IP pool was assigned to you, it was already on a spam list, meaning you might be affected by the activities of other AWS users.
New IP Address: If you used another email sending service before, your emails were sent from a different IP address. Email Service Providers (ESPs) recognize you by that previous IP address. When you start sending emails from AWS, you’re using a new IP address. The ESPs can’t match this new IP address with their records of your sender domain, which can negatively impact deliverability. To mitigate this, it’s better to send a smaller volume of emails initially from the new IP address and gradually increase the amount. This allows ESPs more time to recognize and trust your new IP address.
You can follow these steps:
1. You might have an issue in SPF record, so you need to look into it.
2. Improve your email. Too many images make your email bulky. Bulky emails are tough to deliver and impact deliverability. We have seen customers getting better output by sending simple text emails. It looks like a personal email.
3. Avoid adding any URLs other than your sending domain to your email content. For example, don’t use URL from sendgrid.com or similar.
4. Set Action URL from the Settings > Custom URL section. Add your own domain/subdomain. It will improve deliverability. It’s part of point 3.
5. Personalize your email campaign. For example, it’s better to write Hi {{first_name}}, instead of Hi Guys,. To ESPs, it means you know who you are sending emails to and each email is different.
6. Create email campaigns using drag and drop editor. It creates better HTML code that supports all types of devices and ESPs.
For more detailed information, you can read this blog: https://mailbluster.com/blog/the-ultimate-guide-on-how-to-prevent-your-email-newsletters-from-going-to-spam . If you can follow this correctly, it would definitely help you a lot.