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MBOX PST

Convert MBOX to PST
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Convert MBOX files to Outlook PST in 3 steps. Works with Thunderbird, Gmail, Apple Mail. EU servers, TLS 1.3, auto-delete 48h.

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🛡️ GDPR Compliant 🔒 TLS 1.3 Encryption 🇪🇺 EU Servers 🗑️ Auto-delete 48h

What is a MBOX file?

MBOX (short for Mailbox) is one of the oldest and most universal email storage formats. It stores all emails in a single file, with each message appended one after another, separated by a 'From ' line.

MBOX is the default format used by:
- Mozilla Thunderbird — the most popular free desktop email client
- Google Takeout — when you export your Gmail data, Google provides it as MBOX
- Apple Mail — macOS uses a variant called EMLX, but can export to MBOX
- Postbox, Eudora, SeaMonkey — and many other open-source clients

While MBOX is widely supported, it has limitations: no built-in folder hierarchy (folders are separate files), no native search indexing, and large files can become slow to open. It also lacks encryption support, making it less suitable for archiving sensitive corporate email.

What is a PST file?

PST (Personal Storage Table) is Microsoft Outlook's proprietary format for storing email messages, calendar events, contacts, and tasks. It's the standard archival format for corporate email worldwide.

Key features of PST:
- Folder hierarchy — preserves your complete folder structure
- Rich metadata — retains attachments, read status, flags, categories
- Search-ready — Outlook indexes PST files for instant search
- Password protection — optional encryption for sensitive data
- Universal Outlook support — works with Outlook 2007, 2010, 2013, 2016, 2019, 2021, and Microsoft 365

PST is the go-to format for email archiving, legal discovery (eDiscovery), and migrating between email systems in enterprise environments. A single PST file can hold up to 50 GB of data.

Why convert MBOX to PST?

Converting MBOX to PST is one of the most common email migration tasks. Here are the top reasons:

1. Switching from Thunderbird to Outlook
If your company is moving to Microsoft 365 or you're switching from Thunderbird to Outlook, your existing emails are in MBOX format. Outlook can't read MBOX files natively — you need to convert them to PST.

2. Importing Gmail backup into Outlook
Google Takeout exports your Gmail as MBOX files. To import these into Outlook for backup or migration purposes, you need PST format.

3. Corporate compliance and archiving
Many organizations require email archives in PST format for legal discovery (eDiscovery), auditing, or long-term compliance storage.

4. Better organization
PST preserves folder hierarchy, which MBOX doesn't natively support. Converting to PST gives you a clean, organized email archive.

MBOX vs PST — Key Differences

Feature MBOX PST
File structure Single file, all emails concatenated Structured database with B-tree indexes
Folder hierarchy Not natively supported (separate files) Full folder tree preserved
Max file size No hard limit (performance degrades) 50 GB (Outlook 2010+)
Email clients Thunderbird, Apple Mail, Postbox, Gmail Microsoft Outlook (all versions)
Attachments MIME-encoded inline Extracted and indexed separately
Search Requires external indexing Native Outlook search integration
Encryption Not supported Password protection available
Calendar/Contacts Email only Email, calendar, contacts, tasks

3 methods to convert MBOX to PST

Method 1: Manual import via Outlook

Open Thunderbird, select emails, save as EML files, then import EML files one by one into Outlook. This is the free but tedious approach.

Pros

  • ✓ Free
  • ✓ No third-party software needed

Cons

  • ✗ Extremely slow for large mailboxes
  • ✗ Loses folder structure
  • ✗ Manual process prone to errors
  • ✗ Requires both Thunderbird and Outlook installed

Method 2: Desktop conversion software

Several desktop applications can convert MBOX to PST on your local machine. These paid tools typically cost between $29 and $199 per license.

Pros

  • ✓ Preserves folder structure
  • ✓ Batch conversion support

Cons

  • ✗ Expensive ($39-$199 per license)
  • ✗ Windows only
  • ✗ Software installation required
  • ✗ Slow for large files (local processing)
Recommended

Method 3: MailtoPst (online, free trial)

Upload your MBOX file to MailtoPst, select PST as the output format, and download the converted file. No software to install, works from any browser.

Pros

  • ✓ First conversion free
  • ✓ No installation needed
  • ✓ Works on Mac, Windows, Linux
  • ✓ EU servers, GDPR compliant
  • ✓ Handles files up to 51 GB
  • ✓ Preserves folder structure and metadata

Cons

  • ✗ Requires internet connection
  • ✗ Paid credits after first free conversion
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Step by step

How to convert MBOX to PST with MailtoPst

01

Upload your MBOX file

Drag & drop or click to upload your .mbox file. Files up to 51 GB supported with resumable upload.

02

Choose PST as output

Select PST from the format dropdown. MailtoPst auto-detects the best conversion settings.

03

Download your PST file

Conversion takes seconds. Download your .pst file or receive it by email.

Convert your MBOX to PST now →

First conversion free. No credit card required.

FAQ

Frequently Asked Questions

Can I convert MBOX to PST for free?

Yes. MailtoPst offers your first conversion completely free, with no credit card required. After that, credit packs start from €4.99 for 5 conversions.

Will the conversion preserve my folder structure?

Yes. MailtoPst preserves the complete folder hierarchy, email headers, attachments, read/unread status, and all metadata during conversion.

How long does the MBOX to PST conversion take?

Conversion time depends on file size. Most files under 1 GB convert in under a minute. Larger files (5-50 GB) may take a few minutes. MailtoPst uses cloud processing for fast results.

Is it safe to upload my MBOX file?

Absolutely. Your files are processed on European servers (France & Netherlands), encrypted with TLS 1.3 in transit, and automatically deleted after 48 hours. We never read, analyze, or share your data.

Can I convert a Gmail MBOX export to PST?

Yes. Google Takeout exports your Gmail as MBOX files. Simply upload the .mbox file from your Google Takeout archive to MailtoPst and convert it to PST for use in Outlook.

What versions of Outlook are compatible with the converted PST?

The PST files generated by MailtoPst are in Unicode PST format, compatible with Outlook 2007, 2010, 2013, 2016, 2019, 2021, and Microsoft 365.

Related conversions

EML → PST EMLX → PST MSG → PST OLM → PST OST → PST PST → MBOX
See all 30 conversion paths →

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