Allowlists
Add an IP address to your allowlist
Help prevent messages from certain IP addresses from being marked as spam by adding them to an email allowlist. Messages from these addresses won't be marked as spam by Google Workspace.
Email allowlists are always applied to your entire domain. You can’t create email allowlists that apply to specific organizational units only.
1. Sign in to your Google Admin console.
https://admin.google.com/
2. From the Admin console Home page, go to Apps > Google Workspace > Gmail > Spam, Phishing and Malware.
3. On the left, select the top-level organization. This is usually your domain.
4. On the Spam, phishing, and malware tab, scroll to the Email allowlist setting.
5. Enter the IP address of the sending mail server(s) you want to add to the allowlist.
The IP address information will be provided by TreeTop Security.
6. At the bottom of the page, click Save.
Note: It can take up to 24 hours for your changes to take effect. You can track changes in the Admin audit log.
https://support.google.com/a/answer/4579579
The text from this guide was copied from the Google Workspace Admin Help found below. Please check there for the latest instructions.
https://support.google.com/a/answer/60751?hl=en