Operion Mail - Standard - Sending limits

To keep our systems healthy and your accounts safe, all Google Apps account limit the amount of mail a user can send. The limits restrict the number of messages sent per day and number of recipients per message. After reaching one of these limits, a user cannot send new messages but can still receive incoming email.
The restriction on sending new mail typically lasts for one hour, but can last as long as 24 hours. A user can access and use the account normally after this period, at which time the sending limits are automatically reset.
The following limits apply for Google Apps for Business or Education editions. Sending limits for Google Apps for Business trial users are lower than those in the table below. The value of these limits may change without notice in order to protect Google’s infrastructure.
Sending limits

Limit type	Description	Value
Messages per day	Daily sending limit*	2000
Messages auto-forwarded	Messages automatically forwarded from another account; not included in the daily sending limit	10,000
Auto-forward mail filters	Account filters that automatically forward mail	20
Recipients per message	Addresses in the To, Cc, and Bcc fields of a single email*	2000 (500 external)
Recipients per message (sent via SMTP by POP/IMAP users)	Addresses in the To, Cc, and Bcc fields of a single email*	100
Total recipients per day	Individual addresses count in every mail sent; 5 emails sent to 10 addresses count as 50 recipients*	10,000
External recipients per day	Email addresses outside your primary domain. Includes domain aliases and alternate domains.	3000
Unique recipients per day	Individual addresses count once a day; 5 emails sent to 10 addresses count as 10 unique recipients*	3000 (2000 external)

*applies to both internal and external recipients