How to flash Samsung firmware

A full Samsung firmware package contains up to five files. Which ones you flash decides whether your data survives.

The files in the package

File	Contains	Flash it?
`BL_…tar.md5`	Bootloader	Yes
`AP_…tar.md5`	Android system, kernel, recovery	Yes
`CP_…tar.md5`	Modem / radio firmware (missing on Wi-Fi tablets)	Yes, if present
`CSC_…tar.md5`	Region settings and a full repartition – wipes all data	Only for a clean install
`HOME_CSC_…tar.md5`	Region settings, keeps your data	For an update without data loss

Before you start

Back up your data. Even with HOME_CSC, a failed flash can force a reset.
Charge to at least 50 % and use a direct USB cable, not a hub.
Know your Google account password: after a reset, Factory Reset Protection (FRP) asks for it.
Check the bootloader bit – a lower bit than your current one will be rejected.

Enter download mode

On most current Galaxy phones: switch off, then hold Volume Up + Volume Down while plugging in a USB cable connected to the computer, and confirm with Volume Up. Older devices with a Bixby or Home key use different combinations.

Option A: Odin (Windows)

Install the Samsung USB driver and open Odin as administrator.
Load BL, AP, CP and either HOME_CSC (keep data) or CSC (clean install) into the matching slots. Loading AP takes a while.
Leave the default options; do not tick “” unless you also load a PIT file and know why.
Click Start and wait for PASS. The device reboots on its own; the first boot can take 10 minutes.

Option B: samloader (Windows, macOS, Linux)

samloader can also flash, without Odin and on any desktop OS:

samloader detect --wait
samloader flash --help

Pass the BL and AP packages (for example -b BL_….tar.md5 -a AP_….tar.md5) plus CP and CSC as described in its help.

If something fails

“” / “” error: the firmware's bootloader bit is lower than the device's. Use a build with the same or higher bit.
Stuck at “”: try another cable or USB port, reinstall the driver.
Boot loop after HOME_CSC: boot into recovery and wipe the cache partition, or flash again with CSC (data loss).