What is the email attachment size limit?

Simple answer is 100MB (Text + Attachments).

But there are other limits that could prevent you to send large message.

Outlook limit

Outlook's send limit is 20MB.

You can follow this guide https://is.gd/uPZZcu to increase the limit.

We do not recommended to change system default settings

Other email clients, such as Android/iPhone/Thunderbird/Foxmail may also have their limit.

SXL mail server limit

Our email server's limit is 100MB. This cannot be changed.

You can send this large message only via our WebMail when the recipient is also on our mail server.

Recipient's limit

Different company have different limits. Below are limits of some big companies:

Gmail 25MB
Outlook.com 20MB
Yahoo Mail 25MB
Most large companies 5-15MB

Reference: https://cdn.sxl.net/25/251746818998.jpg

How to send large attachments to my receivers?

There are several methods.

1. Upload your file to your personal Google Drive or Microsoft OneDrive, and then share the link. (This is the recommended solution)

How to share file on Onedrive: https://is.gd/jqFSFX or https://youtu.be/Z6qpwTI5lRI

How to share file on Google Drive: https://is.gd/ZLyljO or https://youtu.be/ElabHPB3Urw

2. Use a public send big files for free service.

If you are sending confidential documents via any of them. Please ZIP the file with a password first.

3. If you often need to send large files, such as product catalogues, SXL can offer a web application (for a fee) for this function.

Technical

Mail servers only care about a message's total size (content + attachments + overheads). The actual attachment size limit is roughtly 98% of the above mentioned size.

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