Install /e/OS on a Fairphone FP5 - “FP5”

The instructions in this guide will assist you to install /e/OS on your FP5. Please read through the instructions at least once before actually following them, so as to avoid any problems later.

It is important that you know that downgrading Smartphones on OS versions greater than the /e/OS OS version you plan to install, can cause instability or at worst brick some devices. We recommend that you check your current OS version, before attempting the installation.

It is advisable to flash your device only if you know what you are doing and are ok taking the associated risk. All /e/OS builds are provided as best effort, without any guarantee. The /e/OS project and its project members deny any and all responsibility about the consequences of using /e/OS software and or /e/OS services.

Requirements

  • If required take a backup of all important data from your phone on an external storage device before proceeding.
  • Do not take a backup on the same device as some of these actions will format the device and delete the backup.
  • Ensure your phone is charged more than 50%
  • Check that adb and fastboot are enabled on your PC. If not you can find the setup instructions here
  • Download all the files and images mentioned in the download section below before starting the installation

  • Make sure you have a working data cable to connect your device to the PC. There are cables which are only for charging and do not transfer data.

  • Your device requires a code to unlock the bootloader. Get the code here before proceeding with the next steps

  • Enable USB debugging on your device. You can find the instructions here
  • Make sure that your model is listed in the Smartphone Selector. Check the model supported. Where available, information on the model supported should show as a pop-up when you hover the cursor on the Device name. The model number supported should be the exact same.
  • Boot your device with the stock OS at least once and check every functionality.
Warning: Make sure that you can send and receive SMS and place and receive calls (also via WiFi and LTE, if available), otherwise it will not work on /e/OS as well. Additionally, some devices require that VoLTE/VoWiFi be utilized once on stock to provision IMS.

Please share your experience , suggest tips or changes to this install guide documentation by visiting the FP5 specific topic on our community forum.

To report issues in /e/OS please refer this guide

Caution: The FP5 comes with an anti-rollback feature. Google Android anti-roll back feature is supposedly a way to ensure you are running the latest software version, including the latest security patches.

If you try installing a version of /e/OS based on a security patch that is older than the one on your device, you will brick your device. Click on Details below for detailed information

To check the security patch level on your phone with a locked bootloader, prior to installing /e/OS, open your phone Settings » About Phone » Android Version » Android Security Patch Level.Then compare it against the level of the security patch on the /e/OS build as visible in the Downloads for FP5 section below.

The following values control whether anti-rollback features are triggered on FP5:

* Rollback protection errors trigger if you install an update whose version number is LESS than the rollback index’s value stored on device.
* The value of rollback index is UPDATED to match ro.build.version.security_patch’s value of the currently installed version, but only if the bootloader is LOCKED.
* The value of rollback index is NOT dependent on the currently installed ANDROID VERSION.
* The value of rollback index can NEVER be DOWNGRADED.
* Rollback protection errors are FATAL when the bootloader is LOCKED.
* Rollback protection errors are IGNORED when the bootloader is UNLOCKED.

Here are some examples to help you understand how anti-rollback features work:

Example 1
* Your FP5 with Google Android has a Security Patch Level saying June 5, 2025
* The /e/OS build available says: /e/OS build : A15 official (Security patch: 2025-05-05)
* In this example, the /e/OS build has an older Security Patch level than the origin, so the anti-roll back protection will trigger, and you will brick your phone
Example 2
* Your FP5 with Google Android has a Security Patch Level saying June 5, 2025.
* The /e/OS build available says: /e/OS build : A15 official (Security patch: 2025-06-05)
* In this example, the /e/OS build has the same Security Patch level than the origin, so the anti-roll back protection will pass, and you will be able to install /e/OS with no issues.

Example 3
* Your FP5 runs Google A15 while /e/OS is now available based on A14.
* Your FP5 with Google Android has a Security Patch Level saying 2025-10-03 or October 3rd, 2025.
* The /e/OS build available says: /e/OS build : A15 official (Security patch: 2025-06-05)
* In this example, the /e/OS build has an older Security Patch level than the origin, so the anti-roll back protection will trigger, even if the /e/OS version runs on a more recent version of AOSP. In this example, you will brick your phone.

Downloads for FP5

To understand the difference between /e/OS builds check this guide

Warning: Please note some of the above links can lead to external sites

Unlocking the bootloader

Tip: The steps given below only need to be run once per device.
Warning: Unlocking the bootloader will erase all data on your device! Before proceeding, ensure the data you would like to retain is backed up to your PC and/or an online drive
Warning: Some vendors/manufacturers prevent the bootloader from being unlocked. Depending on where your device was acquired you may or may not be able to unlock the bootloader. To verify if your device is compatible please check the devices list.
  1. Boot the device
  2. Enable and connect Wifi
  3. Enable Developer options
  4. From developer options, enable OEM unlock
    • Get the unlock code from this site and enter it

  5. Reboot on fastboot by running the command in the PC console adb reboot bootloader

    Tip: All the console commands are run on an adb enabled PC and in the adb console.
  6. Ask for unlock with fastboot flashing unlock
  7. Approve with volume + then power
    • The device proceed with a factory reset, and automatically reboots
  8. Reboot again into bootloader
  9. Unlock critical with fastboot flashing unlock_critical
  10. Approve with volume + then power
    • The device proceeds with a factory reset, and automatically reboots

Installing /e/OS

Tip: For Windows users, we advise to use Git Bash. For more info about Downloads and Installation see Official Documentation

  • The FP5 comes with an anti-rollback feature.

  • Please read the paragraph marked 'Caution' in the Requirements section of this guide before proceeding to install /e/OS on your FP5 .

Let’s proceed with the installation:

  1. Unzip the file you downloaded from the link in the Downloads for FP5 section above.

     unzip <fileyoudownloaded>

    In the command given above, replace <fileyoudownloaded> with the name of the file you downloaded. You can unzip the file using a File Manager/File Explorer.

  2. Confirm that the folder where you unzipped the files contains the following :

    • bin-linux-x86 directory - which contains linux tools including fastboot and adb
    • bin-msys directory - which contains Windows tools including fastboot and adb
    • .img files - The .img files that are to be flashed onto the device.
    • flash_FP5_factory.sh - The installer script.

  3. Next boot your FP5 into bootloader/fastboot mode using this key combination

    • With the device powered off
    • hold Volume Down + Power

  4. Now we will run the installer script in a terminal on a Linux PC or in Git Bash UI if the desktop OS is Windows.

    • Make sure you are in the current directory which contains the flash_FP5_factory.sh file.

    • To execute the chmod command as suggested in the next step you may require root or sudo privileges.

    • Linux
      • Right click -> Open terminal here
      • Execute the following command which makes the file executable and starts the installation process

      chmod +x flash_FP5_factory.sh && ./flash_FP5_factory.sh

    • Windows
      • Right click -> Git Bash here
      • Execute the following command which makes the file executable and starts the installation process

      chmod +x flash_FP5_factory.sh && ./flash_FP5_factory.sh

  • After installing all the required files the device will reboot.

Locking the Bootloader

After you have completed the installation and verified it starts up successfully, you can lock the bootloader on your FP5. This will factory reset your device again.

Warning: The bootloader is lockable in official builds only. The procedure to lock the bootloader will not work on community builds.
  • The FP5 comes with an anti-rollback feature.
  • Please read the paragraph marked 'Caution' in the Requirements section of this guide before proceeding to install /e/OS on your FP5 .
  1. Reboot your device into bootloader, via a key combination:
    • With the device powered off
    • hold Volume Down + Power
  2. In the command prompt, lock critical partition with the following command
    • fastboot flashing lock_critical
    • Approve with Volume + then power
  3. In the command prompt lock the device with the following command
    • fastboot flashing lock
    • Approve with Volume + then power
  4. Now the device will reboot into /e/ OS
Success: Congratulations !! Your phone should now be booting into /e/OS !!

Please share your experience , suggest tips or changes to this install guide documentation by visiting the FP5 specific topic on our community forum.

To report issues in /e/OS please refer this guide