What Are the Yahoo Mail Message and Attachment Size Limits?
Yahoo Mail sends emails up to 25 MB in total size. This size limit applies to both the message and its attachments. If an attachment is exactly 25 MB, it won’t go through because the text and other data in the message add a small amount of data.
How to Reduce the Size of a Message
If a message you are about to send in Yahoo Mail exceeds the limit, you can employ a number of strategies to reduce its size:
Compress the attached files using an archiving utility. If you have multiple files to send, attach them to more than one message. Send a link to where the recipient can download the file.
How to Send Larger Files
To send a file larger than Yahoo Mail allows, use a file sending service, or upload it to Dropbox and send a link to the file using Yahoo Mail.
