How to upgrade Xiaomi Redmi 9S to the current version of MIUI: 3 proven ways

Why it’s important to update the firmware on Redmi 9S and what it does

Smartphone Xiaomi Redmi 9S (The codename curtana was released in 2020, but is still used due to its balanced characteristics: the Helio processor. G35, 4GB of RAM and a 5020mAh battery, but even this hardware requires regular software updates.The manufacturer releases security patches, fixes bugs and sometimes adds new features through updates. MIUI.

What does concretely do with the firmware update? First, the latest version of MIUI 14 (Android 12) for the Redmi 9S closes critical vulnerabilities from 2023-2026 that could allow attackers to access your data via Wi-Fi or Bluetooth. Second, it optimizes battery life – many users note that after upgrading to MIUI 13.0.4+, the smartphone has become less likely to overheat when charging. Finally, new versions often bring improvements to the camera (for example, better HDR processing) and interface.

But there are pitfalls. Some upgrades can slow down older models, and the wrong firmware through Fastboot can turn a phone into a brick. So before you upgrade to the Redmi 9S, it's worth weighing the pros and cons -- and follow the instructions exactly.

Method 1: Automatic Air Update (OTA)

The simplest and most secure method is an over-the-air update (OTA), which requires no PC connection and is suitable even for beginners, and the system will find the actual firmware and install it with minimal risk.

To check for updates:

1. Open Settings → About the phone → System update.
2. Click on the three dots in the top right corner and select Download the latest updates.
3. If the update is available, click Download (Wi-Fi or mobile internet required).
4. After downloading, select Reboot and Update.

⚠️ Note: If you have custom firmware installed (e.g. LineageOS or Pixel Experience), OTA-Updates may not work or cause a failure.In this case, use methods 2 or 3.

Charge your phone at least 50% | Connect to stable Wi-Fi |Free 2–3 GB of storage |Disable VPN and proxy | Backup important data-->

The download speed depends on Xiaomi servers. If the update is 0% or 99%, try:

• 🔄 Restart the phone and try again.
• 📶 Switch from mobile to Wi-Fi (or vice versa).
• 🕒 Wait a few hours – sometimes the servers are overloaded.
• 🛠️ Clear the cache of the application System Update in Settings → Annexes → Application management.

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OTA-Updates are the safest way, but they come with a delay (sometimes 1-2 months after the official release).

Method 2: Manual installation via Recovery Mode

If OTA doesn't work, or if you want to install the firmware immediately after it's released, you can download the update file manually and flash it through the receptacles, which is suitable for official MIUI firmware (not custom!).

Steps:

1. Download the correct version of the firmware for Redmi 9S (curtana from the official website: 🌐 Official archives MIUI (Choose Stable for stable version or Developer for beta). 📁 The file must have a name of the type miui_CURTANAGlobal_V14.0.2.0.SJFMIXM_... and extension.zip.

Transfer the downloaded file to the root folder of the phone’s internal memory (not to folders!).

Volume up + Nutrition

Recovery Mode

Install update.zip to System

Confirm the installation and wait for completion (5-10 minutes).

⚠️ Note: Do not try to flash firmware from another model (for example, from Redmi). 9A or Redmi Note 9S) — This will cause a hard brick, and always check the code name of the device (curtana for Redmi). 9S) file-name.

Method 3: Fastboot Firmware (for power users)

This method requires a computer and a Mi Flash Tool program, and it's useful if:

• 🔧 The phone is not switched on (soft brick).
• 🔄 We need to revert to an older version. MIUI.
• 🛡️ Requires a clean installation without traces of previous firmware.

Instructions:

1. Download Fastboot firmware for curtana from the official website (the file will be in.tgz format).
2. Unpack the archive in a folder on a PC (for example, C:\curtana_fastboot).
3. Install the Xiaomi USB Drivers and Mi Flash Tool (you can download on the official page).
4. Turn off the phone, then press Volume Down + Power to enter Fastboot Mode (a hare in a hat-eared hat will appear).
5. Connect your phone to your PC through USB-cable.
6. Launch the Mi Flash Tool, press Select and specify the folder with the unpacked firmware.
7. Select Clean All or Clean All and Lock (if you want to lock the bootloader after you have been firmware).
8. Press Flash and wait until it is completed (10-15 minutes).

⚠️ Note: If you choose clean all and lock, the phone bootloader will be locked and further firmware manipulation will require official unlocking via the Mi Unlock Tool (the process takes up to 720 hours of latency!).

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Before you run your Fastboot, disable the antivirus on your PC – it can block Xiaomi drivers as “suspicious.”

Frequent update errors and how to fix them

Even if you follow instructions, you can get into trouble, and here are the most common problems and solutions.

• ❌ "Couldn't verify update" error: Reason: corrupted firmware file or model mismatch Solution: Download the file again (check checksum) MD5) Or make sure that the firmware is for curtana.
• ❌ The phone is stuck on the logo. MI after the update: Reason: Data conflict between old and new firmware.Solution: Go to Recovery Mode and select Wipe Data → Wipe All Data (complete reset).
• ❌ Mi Flash Tool shows "flash is not done": Reason: wrong firmware mode or driver problems Solution: Try another USB-Cable/port, reinstall drivers or select clean all mode instead of clean all and lock mode.

If your phone is slower after the update, try:

1. Clear the cache in Recovery Mode (Wipe Cache).
2. Reverse to the previous version of MIUI (if there is a backup).
3. Reset the settings to factory (pre-save the data!).

How to check the success of the update and version of MIUI

After you restart the phone, you need to make sure the firmware is installed correctly.

1. Open the Settings. → The phone.
2. Check the fields: MIUI version (e.g. MIUI Global 14.0.2 Stable) Android version (should match firmware, e.g. Android 12) Security patch level (current month/year, e.g. May 5, 2026).

Run several applications (camera, browser, settings) – they should work without failure.

If the MIUI version has not changed, the update has not been installed.

• 🔄 Repeat the process (for the purpose of OTA or recovery).
• 📱 Check if the date/time settings are lost (they may block the installation).
• 🛠️ Try another method (e.g. Fastboot instead of Recovery).

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After a successful update, it is recommended to make a cache reset in Recovery Mode - this will eliminate possible lags and application errors.

Should the Redmi 9S be updated in 2026?

The relevance of the Redmi 9S updates in 2026 is not so clear: on the one hand, Xiaomi officially stopped supporting the device in 2023, which means that new versions of MIUI (for example, MIUI 15) will not be for it.

Pros of updates:

• 🔒 Closing security vulnerabilities (relevant if you use mobile banking).
• 📱 Correction of bugs with connection to Wi-Fi/Bluetooth.
• 🎮 Optimize performance in games (for example, in Free Fire or Call of Duty Mobile).

Cons:

• ⚠️ New versions MIUI They can be “slowed” on the old iron (especially the old one). MIUI 13/14).
• 📴 Some features (such as Super Wallpapers) are not stable.
• 🔋 Increased battery consumption due to background processes.

If your Redmi 9S runs on your current firmware and you don’t use critical apps (banks, payments), you can stay on the latest proven version. For enthusiasts, custom firmware like LineageOS 20 (based on Android 13) is an alternative, but they require an unlocked bootloader and experience.

FAQ: Answers to Frequent Questions