How to Compress Outlook PST Files in 2025

[Ryancooper]

Compress Outlook PST files to optimize storage space and improve Outlook performance. The manual process involves reducing the file size by deleting unnecessary items and compacting the PST file. While this method is straightforward, it has challenges. Manual compression requires time and may not achieve significant size reduction if duplicate items or oversized attachments are present. Additionally, there’s a risk of data corruption if the PST file is already close to its maximum size. Managing multiple PST files manually can also be cumbersome.

To simplify the process, the Migrate Cloud Data PST Compress Tool offers an efficient solution. This tool automatically identifies and removes unnecessary data, compresses attachments, and reduces file size without compromising data integrity. It also supports batch compression, making it ideal for managing multiple PST files. Using this tool eliminates the risks associated with manual methods and ensures a seamless compression process.

[kikowap]

Are you looking for how to compress Outlook PST files in 2025? here I share with you the most reliable solution which is the OSTTOPSAPP Compress Outlook PST Tool. It supports all versions of MS Outlook. It easily compresses Unicode and ANSI PST files. It deletes unnecessary data to protect PST files from getting corrupted. No need for tools to install MS Outlook to compress PST files. It supports all versions of MS Outlook and Windows OS.

[robertroot123]

If you need to compress Outlook PST files easily, download the MacSonik PST Compress Tool. Using this helpful solution, users can compress single and multiple large PST files in a single click and save the Outlook data file from corruption. It enables users to reduce PST file size in batches with zero data alteration. Moreover, users can split PST files and save them without any data modification. They can set the desired size of the resultant PST files in MB and GB.

[thomasharris]

I was facing a lot of problems with Outlook's slow speed and heavy PST files. Tried many methods, but nothing made much difference. Then I came to know about the Compress Outlook PST Tool.

With this tool, I compressed my 12 GB file to just 6 GB without any data loss. The best part—it is very user-friendly; no technical knowledge is required.
Option to remove attachments
Can remove duplicate data
Works even without installing Outlook
 
If you are also troubled by Outlook's slow speed, then definitely try it once. I got a lot of benefit."

[lilyparker]

I recently used ToolsBaer PST Compact Software to reduce the size of the Outlook PST file, and to be honest, the result was quite good. My PST file was over 6GB, which caused Outlook to hang frequently. The special feature of this tool is that it compresses files without any data loss. The interface is quite simple, and no technical skills are required.

It has different modes like:
Save attachments separately
Remove duplicate data
Compact multiple PST files simultaneously

I tested with the trial version and then purchased the full version. Now Outlook is running smoothly.