5.2.2: submission quota exceeded

What it means

Exchange Online limits both how many recipients a mailbox can address in 24 hours and how many messages it can submit within a set period. Going over either produces 5.2.2 Submission quota exceeded. Microsoft also documents a related report without a code, saying the sender's submission quota was exceeded, tied to a limit of 10,000 recipients per day. As with 5.1.90, an unexpected hit on these limits often means the account was compromised. Other servers use 5.2.2 for a full mailbox; the wording tells the two apart.

Common causes

• The account sent to more recipients in 24 hours than its limit allows.
• An application submitted messages faster than the message rate limit.
• The account is compromised and sending spam.

How to fix it

1. 01If the volume was legitimate, wait a day before sending again and spread future sends out.
2. 02If you did not send the messages, reset your password, scan your devices and tell your admin.
3. 03Admins: check the account for inbox rules, forwarding and delegates added by an attacker, following Microsoft's compromised account steps.
4. 04Move bulk or application mail to a service designed for it.

Sources

What this page rests on, checked on 20 Oct 2026. The explanation is ours; the reply text is the server's.

• Email nondelivery reports and SMTP errors in Exchange Onlinelearn.microsoft.com
• Fix NDR error "the sender's submission quota was exceeded" in Exchange Onlinelearn.microsoft.com
• Exchange Online limitslearn.microsoft.com

Further reading

• The standard meaning of 5.2.2: mailbox full