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Stagger mass communications over 2 days
Send messages to one group of recipients, wait 24 hours, and then send to another group.
Send mail to a group address
Send mail to many email addresses using a single group address. For example, contact all users in your organization by adding everyone in the domain to an email list. For more details, see Groups and Group policies and limits.
Use a Marketplace solution
Many third-party developers offer apps for sending bulk mailings. For ideas, go to the G Suite Marketplace.
Note: Google does not offer technical support for Marketplace apps. Marketplace solutions are created by third-party developers for a general audience.
Build an App Engine solution
Developers can increase mail limits by building a customized application. See App Engine for mail.
Use a local mail server
If you have a local mail server, use it to send mail directly to recipients to avoid sending limits. This local server should also be added to your SPF record to stop the messages from being marked as spam.
Review bulk sending guidelines and best practices
Some email recipients might report bulk messages as spam. Therefore, you need to ensure that all recipients are willing to receive the emails. You can also check email settings for any incorrectly configured forwarding rules or filters. For details, see our bulk sending guidelines and best practices.