How to reflash Xiaomi Redmi 9T: official and custom firmware

Reflashing Xiaomi Redmi 9T (codenamed lime) may be required to install a fresh version of MIUI, switch to custom firmware (like LineageOS or Pixel Experience), or to restore the device to work after a failure. The process seems complicated only at first glance - with proper preparation and following the instructions, the risks are minimized. However, it is important to understand that any manipulation of the firmware voids the manufacturer's warranty and can lead to data loss if you do not backup in advance.

In this article, we will discuss all the current ways to flash Redmi 9T: through the standard update MIUI Updater, manual installation through Recovery, as well as low-level firmware through Fastboot. Separately, we will focus on unlocking the bootloader, a mandatory step for installing informal firmware. If you are a beginner, we recommend starting with official methods and only then experimenting with custom solutions.

Before you start, answer the question: what type of firmware do you need?

1. Flashing preparation: backup and tools

The first and most important step is to save all the data, and the firmware, especially through Fastboot, completely erases the internal memory of the device, and use cloud services (Google Drive, Mi Cloud) or physical copying to your PC to back up:

• 📱 Contacts, SMS, Call log (export through Settings) → Google → Backup)
• 📷 Photo and video (copy folder) DCIM computer)
• 🎵 Music and Documents (check Download and Documents folders)
• 🔑 Logins and passwords (use managers like Bitwarden or 1Password)

Also prepare the necessary tools:

• 🖥️ Windows computer 10/11 (Fastboot will require Mi Flash Tool drivers)
• 🔌 Cable USB Type-C (preferably original to avoid connection breaks)
• 🔋 Battery charge of at least 60% (when discharged during firmware, the device can turn into a brick")
• 📥 Firmware for your model (download only from official sources - see Section 3)

⚠️ Note: If you install custom firmware, make sure it is compatible with your device’s codename – Lime for Redmi. 9T. Redmi 9 Power's firmware will not work!

2.Official Update Methods: MIUI Updater and Recovery

If your goal is to upgrade Redmi 9T to the latest MIUI without risk, use built-in tools. This is the safest method that does not require unlocking the bootloader.

Update via MIUI Updater

Suitable for stable and beta versions of MIUI:

1. Open Settings → About the phone → System update.
2. Click Check for updates.
3. If you have a new version, download it (we recommend using Wi-Fi).
4. After downloading, click Reboot and Update.

If the update doesn’t come automatically, try:

• 🔄 Switch to another region (Settings) → Additionally. → For example, choose India or Russia for global firmware.
• 📡 Connect to another Wi-Fi network (sometimes updates are blocked at the provider level).

Manual installation via Recovery

If you don’t have a MIUI Updater update but you have a firmware file (.zip), use Recovery Mode:

Download the official firmware from the site MIUI Download|Rename the file to update.zip and put it in the root of memory.|Disable Find My Device protection in settings|Charge your phone at least to 70%-->

1. Turn off the device.
2. Press Volume Up + Power before the Mi logo appears.
3. From the Recovery menu, select Install update.zip to System (use volume buttons for navigation).
4. Confirm the installation and wait until the process is completed (don’t interrupt!).

⚠️ Warning: If your phone has been stuck on the Mi logo for more than 10 minutes after upgrading via Recovery, reset it via Wipe Data in the same menu.

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Official updates via MIUI Updater or Recovery do not require unlocking the bootloader and retain the Xiaomi warranty.

3.Where to download firmware for Redmi 9T

The firmware source is the key to the stability of the device, and here are the proven options:

For custom firmware, be sure to download additional files:

• 🔐 Magisk (to obtain root rights) – GitHub
• 🛡️ OrangeFox Recovery or TWRP (For customization installations) - orangefox.download
• 📱 Gapps (Google Services for the AOSP-firmware) - OpenGapps

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Before downloading the firmware, check its hash amount (MD5) using the HashMyFiles utility. This will protect against corrupted or fake files.

4. Unlock the bootloader on the Redmi 9T

To install custom firmware or manual updates via Fastboot, you need to unlock the bootloader. Xiaomi officially allows this, but the process takes up to 7 days (due to account verification).

4.1. Linking the Mi Account to the device

1. Register your Mi Account on the official website.
2. On the phone, log in to this account (Settings → Mi Account).
3. Activate synchronization and confirm the phone number.
4. Enable OEM Unlock in Settings → For developers (if there is no item, tap 7 times on the MIUI version in About Phone).

4.2 Unlocking through Mi Unlock Tool

Download the Mi Unlock Tool and follow the instructions:

1. Connect your phone to your PC in Fastboot mode (clip Volume Down + Power when the device is off).
2. Open the Mi Unlock Tool and log in to your Mi Account.
3. The utility will show the lock status. Press Unlock.
4. If you have a waiting time, wait for the time (usually 168 hours).

⚠️ Warning: Once the bootloader is unlocked, all data on the phone will be deleted! also some features (e.g. Mi Pay or Widevine) L1 for Netflix HD) They may stop working.

5. Firmware through Fastboot: step-by-step instructions

The Fastboot method is used to completely reinstall the system, recover from crashes or install official.tgz firmware. Requires an unlocked bootloader and PC.

5.1 Installation of drivers and Mi Flash Tool

Download and install:

• Mi Flash Tool (Windows version)
• Qualcomm HS-USB QDLoader 9008

5.2 Firmware process

1. Unpack the downloaded firmware (.tgz) in a folder without Cyrillic characters.
2. Run the Mi Flash Tool on behalf of the administrator.
3. Connect your phone in Fastboot mode (clip Volume Down + Power).
4. In the utility, click Select and specify the path to the folder with the firmware.
5. Select Clean All (Full Cleaning) or Clean All and Lock (Cleaning + Lock bootloader).
6. Press Flash and wait until it is completed (the process takes 5-10 minutes).

If the Mi Flash Tool is making an error, try:

• 🔌 Use the other USB-port.
• 🖥️ Run the utility in compatibility mode with Windows 7.
• 📥 Download the firmware again (possibly the file is corrupted).

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The Clean all and lock mode in the Mi Flash Tool will lock the bootloader back, only use it if you want to return the official firmware and warranty.

Installation of custom firmware (TWRP + AOSP)

For enthusiasts who want to try Android without MIUI, firmware like LineageOS or Pixel Experience is more complex, but it gives you more customization options.

6.1. Installation of custom Recovery (OrangeFox/TWRP)

Download OrangeFox Recovery for lime from the official website and scroll through Fastboot:

fastboot flash recovery orangefox-recovery.img


fastboot reboot recovery

6.2. Custom OS firmware

1. Copy the firmware (.zip), Gapps, and Magisk (if root is needed) files to your phone.
2. In OrangeFox Recovery, run Wipe → Format Data (enter yes).
3. Install the firmware through Install → Select ZIP.
4. Repeat the step for Gapps and Magisk (if needed).
5. Reboot to the system (Reboot → System).

⚠️ Note: After installing custom firmware, Netflix and other streaming services may work in a reduced quality (due to loss of Widevine certification) L1). To return L1, smear down MIUI backwards.

7. Solving common mistakes

Even with the right instructions, there can be problems, and here are the most common ways to solve them:

If your phone has turned into a brick, try:

• 🔌 Connect to charging for 30 minutes – sometimes helps with battery discharge.
• 🖥️ Flow through EDL Mode (requires an authorized Xiaomi account or boxing).
• 📞 Contact the service center (if nothing above helps).

FAQ: Frequent questions about Redmi firmware 9T