⚠️ Work in Progress: This guide is still under development. Proceed carefully and at your own risk.
This guide is based on the work of u/fit_freak9 — see the original Reddit post for reference.
This process will erase all data and may brick your device if done incorrectly. Proceed at your own risk.
This guide is shared for educational purposes only. It is not official documentation, and I am not affiliated with Samsung or Google.
By following this guide, you agree that:
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You are proceeding at your own risk
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You are fully responsible for anything that happens to your device
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I provide this guide “as is”, with no guarantees or warranties
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I am not responsible for any damage, data loss, device failure, or warranty issues
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Any problems caused by incorrect steps, misuse, or unexpected behavior are not my responsibility
Flashing or downgrading firmware can cause data loss or permanent damage if done incorrectly.
If you do not understand the risks, do not continue.
- Disclaimer
- Guide Overview
- Back Up Your Data First
- Before You Start
- Setting Up Your PC
- Remove Accounts
- Booting into Download Mode
- Flash Firmware with Odin
- Complete the Downgrade
- Notes
- Acknowledgements
In theory, any Samsung device can be downgraded as long as a compatible firmware exists and you can safely access download mode .However, success may vary depending on region, carrier, and current OS version.
Tested Devices:
- Samsung Galaxy S23 Ultra (One UI 8, December Patch)
- A35 (One UI 8, December Patch)
Notes / Limitations:
- Devices must have official firmware available for the target version. (via samfw)
- Carrier-locked devices may fail or require additional steps.
- Downgrading from certain security patches may trigger errors or prevent flashing.
- Always verify your model number (e.g., SM-S918B) and region code before downloading firmware.
This process will wipe all data on your device, including internal storage, apps, and settings.
I recommend using this tools to backup your data.
- Samsung smart-switch (Note: Users have reported battery drain when used to restore data)
- Google Backup
- External drive (via computer)
See the Backup Guide for detailed instructions.
Ensure all requirements below are met before continuing.
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Hardware & System
- Windows PC
- USB-C cable (preferably the original Samsung cable)
Using damaged or low-quality third-party cables may cause connection failures or slow transfer speeds.
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Device Preparation
- USB Debugging enabled (Disabled? See This Guide)
- All accounts removed (especially Google and Samsung)
Failure to do this may lead to failure See: Remove Accounts for more
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Required Software & Files
- Samsung USB Drivers for Windows
https://developer.samsung.com/android-usb-driver - Odin 3.14 (Make sure same version) https://www.odinflash.com/download
- ADB Platform Tools
https://developer.android.com/tools/releases/platform-tools - One UI 6.1 (Android 14) Firmware
⚠️ Download via https://samfw.com
- Samsung USB Drivers for Windows
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Install Samsung USB drivers on your Windows PC.
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Download and extract Odin 3.13.
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Download and extract ADB to a folder (e.g.,
C:\Users\YourUserName\Downloads\platform-tools). -
Extract the firmware file (it should contain files labeled BL, AP, CP, CSC, and HOME_CSC).
Ensure all accounts are manually removed before proceeding, failing to do so may trigger security locks or synchronization errors
- Open Settings and tap Accounts and backup.
- List item
- Tap Manage accounts
- Select the accounts listed
- List item
- Tap Remove account and confirm.
- Repeat for all accounts.
For the Samsung Account: You will usually be asked to enter your Samsung password or verify via a "one-time email" to sign out completely.
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Connect your phone to the PC via USB-C.
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Open Command Prompt, and Enter the command below
cd C:\Users\YourUserName\Downloads\platform-tools
- Verify the connection:
adb devices
Your phone should prompt to allow USB debugging. Select Always Allow. The command should display your device’s serial number.
- Boot into Download Mode:
adb reboot download
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Your phone should restart into Download Mode (a blue screen with a warning).
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Open Odin 3.13 as an administrator.
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Confirm your phone is detected (a blue or green box with “COM” will appear in Odin).
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Load the firmware files:
Click BL and select the file starting with
BL_.Click AP and select the file starting with
AP_(this may take a minute to load).Click CP and select the file starting with
CP_.Click CSC and select the file starting with
CSC_(useHOME_CSCif you want to avoid a factory reset, butCSC_is recommended for downgrading). -
Ensure all boxes in Odin (e.g., Auto Reboot, F. Reset Time) are checked.
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Click Start. The process may take 5–10 minutes.
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Odin will display PASS! in green upon success, and your phone will reboot.
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List item
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If prompted, perform a factory reset:
- Use the Volume Up/Down buttons to navigate and the Power button to select Factory Data Reset.
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Wait for the phone to fully boot (this may take longer than usual).
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Set up your phone as new or restore from your backup.
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Warranty: This process doesn’t void your warranty, and you can upgrade to One UI 7.0 later via official updates.
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Troubleshooting:
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If Odin fails, ensure the correct firmware and USB drivers are used. Try a different USB port or cable.
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If the phone doesn’t boot, retry the process or seek help from a Samsung service center.
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Resources: For Odin or firmware issues, refer to trusted guides on XDA Developers or samfw.com.
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This guide assumes some technical knowledge. If you’re new, watch a video tutorial for visual guidance. I recommend this Guide by Tech Jarves
This guide is a community-based compilation and simplification of existing downgrade methods shared by other users. The steps have been reorganized and rewritten for clarity and ease of understanding.
Primary references used: