Loading

Outbound Email Attachment Limits in Lightning Experience and Salesforce Classic

Date de publication: Apr 22, 2026
Description

When sending emails from Salesforce to customers or colleagues, you may need to attach multiple files such as contracts, presentations, or documentation.

You may encounter one of the following errors when trying to attach a file to an outbound email.

Salesforce Classic: "The file cannot be larger than 10MB."
Lightning Experience: "0 of 10 files selected"

This can happen when using a Salesforce-integrated email application such as the Email quick action or the Send Email button.

NOTE: This doesn't apply for List Email or Mass Email features.

Résolution

The behavior of email attachments is different between Salesforce Classic and Lightning Experience.

 

Salesforce ClassicLightning Experience

More than 10 files can be attached when sending an email, but the total file size can't exceed 18 MB.

NOTE: While 18 MB is the maximum, the user interface currently displays 10 MB. This is related to the following known issue:  Email author shows a limit of 10mb for attachments on outbound emails.

Up to 10 file can be attached at a time when sending an email, but the total file size can't exceed 25MB.

NOTE: 25MB is the hard coded limit

 

Numéro d’article de la base de connaissances

000381295

 
Chargement
Salesforce Help | Article