We have a lot of posts that talk about avoiding being flagged as spam, such as: https://sendgrid.com/blog/10-tips-to-keep-email-out-of-the-spam-folder/ https:/

We have a lot of posts that talk about avoiding being flagged as spam, such as: https://sendgrid.com/blog/10-tips-to-keep-email-out-of-the-spam-folder/ https://sendgrid.com/blog/10-tips-to-keep-email-out-of-the-s... These kinds of articles will be able to provide better advice than I can in a comment thread. One tip, if it is in the budget, is to have two sending IPs. One for transactional mail and one for newsletters. This will let you keep your transactional mail's IP's reputation higher.