I checked out the headers of these emails, and while SPF, DKIM and DMARC all pass, they are getting marked as junk email: X-MS-Exchange-Organization-SCL: 9 To test, I signed up for an outlook account and sent email from my work email address to my outlook account. These emails, regardless of content, go to the Junk email folder. I work for a B2B and since December we have been having trouble with ANY emails that are sent from us (using Google Suite, or Mailchimp, or Salesforce) to outlook/o365 users.