Pre-requisite: Understand the various emails' status.

Deliverability is not an exact science. Each mailbox has its own policy and rules. However, it is possible to optimize a campaign to encourage the recipient's mailbox to consider the message received favorably.

Two methods can help you optimize deliverability:

  1. Use all best practices
  2. Ask for a deliverability audit

Best practices

  • Make sure your recipients are qualified and have authorized access to your mailings.
  • Enter a real sender's name (with a first name)
  • Create a short and unique subject. The goal here is to get as far as possible from a spam template cliché. 
  • Personalize your mailings with nominative tags (first name, last name, society...)
  • The 50 first characters of your mailing are what your recipients read when deciding to open, or not open, your message.
  • Avoid using words related to aggressive advertising (ex: promotion, free, congratulations, save money...)
  • Keep your mail's content simple (avoid using too many images)
  • Use a personalized email address (available with the white label feature)
  • Include brand mentions (organization's name, its address, and a link to unsubscribe from future emails)

Ask for a deliverability audit

If the majority of your recipients share the same domain name (corporate event for example), we recommend that you put our technical team in contact with the IT hosting the recipients' email server to make sure no firewall will block your mailings. You can give your IT our sending IP The deliverability audit is included in the white-label feature. For more information, contact us by clicking on the "?" icon at the top right of your page.


All mailboxes have their own way to read and understand the HTML of an email, so it is possible to see some differences between the email you received and the email you created.