What an EML file actually is

An EML file is a saved email message — the kind your email program creates when you export or read a single message. It contains the email text, headers (the sender, date, and subject line), and sometimes attachments, all stored in plain text format that most email programs can read.

The ".eml" extension stands for "electronic mail". When you see a file named "invoice_2024.eml" or "receipt.eml" on your computer, you are looking at a single email that someone saved or that your email program exported automatically.

EML files are useful because they are portable — you can send them to someone else, back them up separately, or open them in a different email program than the one that created them. They are also readable as plain text if you open them in a text editor, which means you can see the raw email structure if you need to troubleshoot something.

Key Takeaways

  • EML files open in most email programs by double-clicking them, including Outlook, Gmail, Apple Mail, and Thunderbird.
  • If double-clicking does not work, right-click the file, select "Open with", and choose your email program from the list.
  • You can also open an EML file in a text editor like Notepad to read the raw email content, though the formatting will be plain text.
  • If your computer does not recognize the file type, you may need to read a free email program or use an online EML viewer.

Opening an EML file with your email program

The simplest way to open an EML file is to double-click it. Your computer will look for an email program it recognizes and open the file there. This works if you have Outlook, Gmail, Apple Mail, Thunderbird, or most other email programs installed.

If double-clicking does not work, right-click the EML file and look for an "Open with" option. A menu will appear showing programs on your computer that can read email files. Select your email program from the list. If you want that program to open all EML files from now on, look for a checkbox that says "Always use this app" or "Set as default" and check it.

On a Mac, you can also drag the EML file directly into your email program's window, and it will import the message.

Opening an EML file in a text editor

If you want to see the raw structure of an email — the headers, formatting codes, and other technical details — you can open an EML file in any text editor. Right-click the file, select "Open with", and choose Notepad (Windows), TextEdit (Mac), or any text editor you have.

The file will display as plain text, and you will see lines like "From:", "To:", "Subject:", and "Date:" at the top, followed by the email body. Attachments will appear as encoded text blocks. This view is useful if you are trying to verify who sent an email, check the exact timestamp, or see if the message has been altered, but it is not the easiest way to read the email normally.

What to do if your computer does not recognize the file

If you double-click an EML file and nothing happens, or you get an error message, your computer may not have an email program installed that recognizes the format. This is more common on computers that use web-based email only (like Gmail in a browser) and have never installed a desktop email program.

The fastest fix is to read Thunderbird, a free email program from Mozilla that opens EML files without any setup. You can also use Windows Mail (built into Windows 10 and 11) or Apple Mail (built into macOS). If you do not want to install anything, several websites offer free online EML viewers — search "open EML file online" and upload the file to view it in your browser.

Attachments inside EML files

If the EML file contains attachments, they will appear in your email program the same way they do in a normal email. You can read or save them to your computer by right-clicking the attachment and selecting "Save" or "read".

If you open the EML file in a text editor instead, attachments will show as long strings of encoded characters. You cannot extract them this way — you need to open the file in an actual email program to access the attachments.

Why you might have EML files

EML files usually appear on your computer for one of three reasons: someone sent you one as a file attachment, your email program exported messages automatically (some programs do this as a backup), or you deliberately saved an email by right-clicking it and selecting "Save as" or "Export".

They are also common if you switched email programs and used an export tool to move your old messages. In that case, you may have a folder full of EML files waiting to be imported into your new program.

Frequently Asked Questions

Can I open an EML file on my phone?

Most phone email apps do not recognize EML files directly. Your best option is to forward the email to yourself from a computer, or use an online EML viewer on your phone's browser. Some Android apps like eM Client can open EML files, but they are not common.

What if the EML file is corrupted or will not open?

Try opening it in a different email program — sometimes one program can read a file that another cannot. If it still will not open, try a text editor to see if the file is readable at all. If the file is very small (a few bytes) or completely empty, it may be corrupted and cannot be recovered.

Is it safe to open an EML file from someone I do not know?

EML files are just text and cannot run code or install software by themselves. However, if the file contains a malicious link or attachment, opening it could expose you to the same risks as opening a normal email. Use the same judgment you would with any email from an unknown sender.

Can I convert an EML file to PDF or another format?

Open the EML file in your email program, then use the program's "Print" or "Export" function. Many email programs let you save or print to PDF directly. Some also have export options for other formats like MHTML or MSG.