Gmail bandwidth limits
Locked out of your account? G Suite administrators can check the User list in the Google Admin console to find details about which limits you've hit and when access will be restored. In some cases, you can reset the Gmail suspension.
For the health and safety of our systems and your account, all G Suite accounts limit Gmail bandwidth. Some activities that transfer large amounts of data in a short period of time, such as syncing a Gmail account to a mobile phone or mail client, can cause a Gmail account to reach the bandwidth limit.
For recommendations about limits and synchronization, see Sync limits. Reaching the limit triggers a safeguard that temporarily stops IMAP upload for the account.
The following Gmail bandwidth limits apply to all G Suite editions. These limits may change without notice to protect Google’s infrastructure.
Gmail bandwidth limits
|Limit||Per hour||Per day|
|Download with web client||750 MB||1250 MB|
|Upload with web client (includes emails sent via Gmail SMTP)||300 MB||1500 MB|
POP and IMAP bandwidth limits
|Download with IMAP||2500 MB|
|Download with POP||1250 MB|
|Upload with IMAP||500 MB|
To address migration needs, you can download your entire mailbox about 3 times per month.Effects
When trying to sign in to a suspended account, you get an error message on the sign-in page. The suspension typically lasts for one hour but can last up to 24 hours. A user can access and use the account again after the suspension, when the bandwidth limit automatically resets.
Migrations or bulk operations using IMAP
If you exceed the upload bandwidth limit with IMAP, the following recommendations are important:
- Avoid large copy and paste or drag and drop operations when using IMAP.
- If you're migrating, use a supported migration option and avoid using IMAP to upload messages.
- If you need to download a large amount of data, try throttling the tool you're using or download in parts.
Some email clients might try failed actions repeatedly, until they use up the account's bandwidth allowance. To make sure that clients aren't retrying any pending actions, try to recreate the profile or sync relationship on all IMAP clients.
Sharing an account among users
If you have multiple users frequently accessing the same account from various locations, you may reach a Gmail threshold and your account will be temporarily locked down. Learn more.
Reduce email label counts
Reducing the total number of labels in Gmail and the number of labels applied to each email lowers the number of folders and emails your Google Account needs to transfer to your email client. Try to use no more than 500 labels.
Use other resources to transfer and share files
Try an alternative to email when sharing many large files at the same time. Use other Google resources, such as Drive, Sites, Google Photos, and YouTube to reduce the risk of your email account using too much bandwidth.
IMAP bandwidth limits
These guidelines apply to any application that uses IMAP to sync email with Gmail. Those include common email clients, backup tools, and BlackBerry® Internet Service (BIS). Other sync methods count against the sync bandwidth limits.
Manage your IMAP clients
Having multiple clients means every message gets downloaded multiple times, increasing bandwidth consumption exponentially. To manage your IMAP clients:
- Remove or disable unused IMAP clients.
- Quit IMAP clients when not in use.
- Make sure all clients are set up according to the recommended IMAP client settings.
Check for unwanted IMAP clients
Tools or services that back up G Suite data commonly use IMAP to access email. If you use such services, make sure they're configured accordingly. Sometimes, a user or administrator might set up an IMAP client and stop using it without disabling it. Or, they were never aware that a service or tool uses IMAP to access G Suite.
- The administrator should check the Google Admin console and see whether any G Suite Marketplace apps are using IMAP.
If applicable, users should navigate to their Google Accounts authorizations page and revoke any unwanted items under Connected Sites, Apps, and Services and Application-specific passwords.
Change the G Suite password to make sure any sync clients set up using that password can't sign in to the account anymore. Then enable desired clients one by one, a few hours apart to pinpoint any offending client.
Check your IMAP sync settings
If you exceeded the download bandwidth limit with IMAP, the following recommendations are important:
- Sync fewer messages in each label by changing the Folder Size Limits value in the Forwarding and POP/IMAP tab of your Gmail settings.
- Sync fewer labels using the Show in IMAP checkboxes in the Labels tab of your Gmail settings. Try not to sync more than 200 labels.