.MBOX File Extension

There is only one file type that uses the .MBOX extension:

Email Mailbox File

Email Mailbox File
  • Developer N/A
  • Popularity
    3.8 (208 votes)
  • Category Text Files
  • Format Text

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.

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.

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

Software's name License Platforms
Apple Mail Apple Mail Bundled iOSMac
Aryson MBOX to PST Converter Aryson MBOX to PST Converter Free Trial Windows
CoolUtils Total Thunderbird Converter CoolUtils Total Thunderbird Converter Free Trial Windows
GNOME Evolution GNOME Evolution Free Linux
Kernel MBOX Viewer Kernel MBOX Viewer Free Trial Windows
Microsoft Outlook 365 Microsoft Outlook 365 Free+ Mac
Mozilla Thunderbird Mozilla Thunderbird Freeware LinuxMacWindows

Updated: April 28, 2019

Search File Extensions