What is EML File Extension? Know All About EML File

What Does An EML File Contains?

EML file extension is the proprietary format for electronic mail messages. It is developed by Microsoft Corporation. An EML file is basically a text file that follows the RFC 822 (or the updated RFC 2822) standard.

When you export an email from a client like Thunderbird or Windows Live Mail, it is saved as an EML file. These files are highly versatile because they contain:

EML File Attributes:

Email Headers: Sender, recipient, date, time, and subject.
Body Content: The actual message text in plain text or HTML.
Attachments: Embedded files (images, PDFs, docs) encoded in Base64.
Hyperlinks: Any web links included in the original email.

How to Save EML Files from Mail Application?

Steps by Step Guide to Save Emails in EML File Format

Gmail

Gmail allows users to download individual email in .eml file.

Open the email in your browser.
Click the three vertical dots (More) icon next to the Reply button.
Select Download message.
Gmail will automatically save the file in .eml format.

Classic Outlook

Classic Outlook defaults to .MSG, but user can save emails in EML file.

Double-click the email to open it in a new window.
Go to File > Save As.
In the "Save as type" dropdown, select Text Only (.txt).
Manually change the file extension from .txt to .eml when naming the file, then click Save.

Note: Using a tool like SysTools Outlook Converter is recommended for large batches to preserve formatting.

Windows Live Mail

Since Windows Live Mail natively uses EML, you can find them in the file system.

Open the application and select the emails.
Click the File menu > Export email > Email messages.
Select Microsoft Windows Live Mail as the format and click Next.
Browse to a folder and click Finish. All emails will be exported as individual EML files.

Outlook.com / New Outlook

The modern Outlook interface now includes a direct way to download messages.

Open the email you want to save.
Click the More actions (...) icon in the top-right corner of the message window.
Select Download (Web) or Save as (New Outlook Desktop).
Choose Download as EML (or Save as EML). The file will be saved to your "Downloads" folder.

Mozilla Thunderbird

Thunderbird is one of the most EML-friendly clients

Method A (Drag & Drop): Simply select the email(s) from your inbox and drag them directly onto your desktop or a folder on your computer.
Method B (Save As): Select the email, click the Menu (three bars) > File > Save As > File. Choose a folder and ensure the format is set to .eml.
Method C (Bulk): Select multiple emails using Ctrl + A, right-click, and select Save Selected Messages > EML Format.

Outlook Web App (OWA)

This is the easiest method if you are accessing your mail via a browser (outlook.office.com).

Log in to your Office 365 account and open the email you want to save.
In the top-right corner of the email message (not the main browser header), click the three dots (...) for More actions.
Select Download from the dropdown menu.
The email will automatically be saved to your "Downloads" folder as an .eml file.