Understanding Google Mail Sending and Sync Limitations
You can manage your email usage effectively by understanding Gmail's sending and sync limitations, including daily message caps and bandwidth restrictions.
Sending Limits
In order to prevent spam, Google will temporarily disable accounts that send a lot of email in a short time.
It's important to be aware of Google's sending limits:
- Messages per day (2,000)
- Recipients per message (2,000/ 500 external)
- Total recipients per day (10,000)
- External and unique recipients per day (3,000)
For alternatives, consider sending emails through Google Groups, Broadcast Email Messaging, or LISTSERV.
Bandwidth/Sync Limits
Similarly, Google Apps accounts also have limits on bandwidth and sync: "Certain activities that transfer large amounts of data in a short period of time, like synchronizing a Gmail account to a mobile phone or mail client, can cause an account to reach the bandwidth limit." If you're using Google Apps email to send many large files, a better tool that will help you avoid these bandwidth limits is Google Drive sharing.
See Bandwidth limits and Sync limits for more information.