How to Unlock Bootloader and Root Samsung S25 / S25+ / S25 Ultra with Magisk

Rooting your Samsung Galaxy S25 series device will provide you with the operating system running root permissions, and thus, you can install custom ROMs, remove bloatware and improve system performance. Nevertheless, you may encounter some difficulties during this process if you are not careful since the bootloader and custom firmware will be unlocked, and flashing a custom firmware may be required. Read through this guide to ethically root your Samsung Galaxy S25, S25+, or S25 Ultra phone with Magisk.

Important Considerations Before Rooting

Before proceeding, be aware of the following consequences:

• Warranty Void: Rooting permanently voids your device warranty in most regions.
• Loss of Samsung Features: Rooting disables:
  • Samsung Pay & Samsung Pass
  • Secure Folder & Samsung Health
  • Galaxy Watch and older Gear compatibility (S3 or earlier)
  • Google Pay and other Knox-dependent features
• OTA Updates Disabled: This will no longer be updated via official software.
• Potential Banking App Issues: Most of the apps that are already installed on your phone might get blocked by the security features of your phone. That said, even with the Magisk Hide settings implemented, I could see how other apps still would not work properly.
• Irreversible Changes: There are some features, even though you have unrooted your device, that can only be disabled in Knox.
• Bootloader Unlock Warning: To get rid of the warning on your MSM Snapdragon, I would advise you to restore stock firmware in fastboot mode, as it is the only certainty that it will work.

If you are comfortable with the risks, follow the step-by-step instructions below.

How to Unlock the Bootloader on Samsung S25 Ultra

To root your Samsung Galaxy S25, S25+, or S25 Ultra, you must first unlock the bootloader.

Step 1: Enable Developer Options

• Under Settings, tap on About Phone and then move on to the Software Information.
• Click seven times on Build Number on your device until the pop-up message is shown: “You are now a developer.”
• Go back to the Settings menu and choose Developer Options.

Step 2: Enable OEM Unlocking

• Locate OEM Unlocking in the Developer Options section and then toggle the switch on.
• Then, confirm the prompt by clicking on YES.

Step 3: Boot into Download Mode

• Switch off your device.
• Hold the Volume Up + Volume Down buttons and connect your device via USB to a PC.
• Leave the buttons pressed when the warning screen is shown.
• Choose Volume Up to enter Download Mode by clicking once.

Step 4: Unlock the Bootloader

• Hold the Volume Up key for a while in Download Mode to unlock the bootloader.
• Your device will erase all the data and reboot itself.

Your bootloader has been unlocked, and you are now good to route your device.

How to Root Samsung S25 Ultra Using Magisk

Step 1: Download Official Firmware

Get the latest official firmware of your device through SamFirm, Frija, or Samloader. After downloading, separate the AP and BL files.

Step 2: Extract the Boot Image for Patching

1. Open the AP.tar.md5 file using 7-Zip and extract init_boot.img.lz4.
2. Open the BL.tar.md5 file and extract vbmeta.img.lz4.
3. Select both extracted files and compress them into a .tar archive using 7-Zip.
4. Copy this .tar file to your phone.

Step 3: Patch Boot Image with Magisk

1. Download and install the latest Magisk APK.
2. Open Magisk and tap Install.
3. Select Patch a File and choose the .tar file you copied.
4. Once patched, transfer the patched .tar file back to your PC.

Step 4: Flash Patched Boot Image

1. Boot your device into Download Mode.
2. Open Odin on your PC and load:
   • AP: magisk_patched.tar
   • BL, CP, and CSC: Original firmware files (Do NOT use HOME_CSC)
3. Click Start to begin flashing.
4. Once complete, the device will reboot.

Step 5: Finalize Root Installation

1. Install the Magisk App again if needed.
2. Open Magisk and follow the setup prompt.
3. The device will reboot once more, and Magisk will be fully installed.

Conclusion

By rooting your Samsung Galaxy S25, S25+, or S25 Ultra with Magisk, you can have the latest customization and rest, but it is not without risk. Therefore, before doing anything, please keep a copy of the file on your computer, follow each step very carefully, and try to anticipate the effects. The advantages of rooting include the ability to use customized ROMs system modifications as well as improve the performance using Magisk as a means for managing root access safely.