.MBOX File Extension

.MBOX File Extension

File Type

Email Mailbox File

Developer N/A
3.3  |  218 Votes
Category Text Files
Format Text

What is an MBOX file?

An MBOX file is an email mailbox saved in a mail storage format used for organizing email messages in a single text file. It saves messages in a concatenated format where each message is stored after another, starting with the "From" header. MBOX files were originally used by Unix hosts but are now supported by other email applications, including Apple Mail and Mozilla Thunderbird.

More Information

Version 1.x of Apple Mail used MBOX files and stored them in the /​User/​Library/​Mail/​Mailboxes/​ directory. However, Mail 2.0 and later uses the .EMLX format, which separates the messages into individual files so that they can be searched by Spotlight.

Opera Mail, which was discontinued in 2016, also stored messages in the MBOX format.

Common MBOX Filenames

INBOX.mbox - The name given to the primary Inbox mail folder in Apple Mail, the default email program for Mac OS X.

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Programs that open or reference MBOX files

Updated June 21, 2019

Verified by FileInfo.com

The FileInfo.com team has independently researched the Email Mailbox file format and Mac, Windows, and Linux apps listed on this page. Our goal is 100% accuracy and we only publish information about file types that we have verified.

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