Our limits & Why we have them
Email limits
At CK Enterprises UK we have a limit on max email sizes. Including the message & any attachments.
The limit is 20MB. If you need to send larger files, we suggest you use a service such as OneDrive
Importance of limits
Email size limits are used for 3 main reasons:
- Performance. Email systems are not designed to transfer large files. SMTP, the protocol that enables email was designed to for short text messages. Addons have affected support for attachments and other extended features but SMTP itself is not suited for transporting large files (Hence the existence of FTP). In addition, mail transfer agents often scan incoming data for viruses and other potential risks, which also takes resources and affects system performance.
- Security. Email services use a limited number of ports to retrieve data. By limiting the size of emails & any attachments we reduce the risk of DoS style attacks against your service.
- Compatibility. Email limits are common place, almost every email client or provider has an imposed limit, some of which are visible below. By conforming to the lowest email limit we allow for maximum compatibility across multiple services.
iCloud Mail: The size of incoming and outgoing messages (20MB, up to 5GB with Mail Drop turned on)
Gmail: You can send up to 25 MB in attachments. If you have more than one attachment, they can't add up to more than 25 MB. If your file is greater than 25 MB, Gmail automatically adds a Google Drive link in the email instead of including it as an attachment. Learn more about Google Drive attachment sharing settings.
Outlook.com: the combined file size limit is 20 megabytes (MB) and for Exchange accounts (business email), the default combined file size limit is 10 MB.
