When an inbox provider (e.g. Gmail, Outlook) observes emails coming from a new (“cold”) IP address or an unfamiliar domain, they take notice and immediately begin evaluating the traffic coming from that IP address. Since inbox providers treat email volume as a key determining factor when detecting spam, it is best to begin sending a low to moderate volume, eventually working your way up to larger volumes. This gives the receiving email providers a chance to observe your sending habits and record how your recipients are engaging with your emails.
Warm-up Best Practices
The following are the best practices for creating a successful warm-up plan for your OptiMail account(s):
- Gradually send an increasing number of real customer emails over a period of 30 days, increasing the volume of emails by a maximum of 150% from one day to the next.
- When creating IP warm-up target groups, start by selecting your more active and engaged customers – to ensure the highest probability of opens and clicks, and the lowest probability of customers marking your emails as spam. For example, you could initially send emails to target groups of Active customers with low values for customer attributes such as “Days Since Last Opened” and “Days Since Last Clicked.”
- Avoid including common spam trigger words and phishing phrases in the subject and body of your customer emails (you can find one list of such words to avoid here).
- Use a spam checker before sending a new email template (IsNotSpam.com is one such free online spam checker).
These precautions will help ensure that the warm-up plan’s maximum number of daily emails is not exceeded and that customers targeted during this period are less likely to unsubscribe and/or report your emails as spam.
Syncing Unsubscribes During the Warm-up Period
If you plan on continuing to send customer emails from your previous email system during the warm-up period, it is important to promptly update any customer unsubscribe requests across both systems. Discuss this with your CSM to ensure that all unsubscribe requests are honored during the 30-day warm-up period. After this period, you will exclusively use OptiMail to send customer marketing campaigns, so this will only be a temporary issue.
Please note:
For uploading your list of historic suppression contacts in the Settings area (for example, hard bounces and unsubscribes), you must complete this process 2 days before the IP warm-up. This is because the IP Warm-Up relies on the batch data process. If the list is uploaded too late, the warm-up process will be delayed.