
Every official firmware build for SM-L310N, newest first: one row per build with all regions (CSC) that received it.
Box codes of SM-L310N for different colors and markets. Firmware is chosen by the model code SM-L310N and your region (CSC), not by the SKU.

SM-L310

SM-L320

SM-L340

SM-L505F

SM-L715F
You can find the firmware on the model: SM-L310N page.
Yes, all firmware files for SM-L310N are 100% official, original, and obtained directly from Samsung servers.
To flash SM-L310N, you need to download the appropriate firmware, put your device into Download Mode, and use the Odin tool to load the BL, AP, CP, and CSC files.
Downgrading is only possible if the bootloader version (binary bit) of the old firmware matches the current one. Always check the binary version before flashing SM-L310N.
Yes. Every build on this page is the official stock ROM for SM-L310N from Samsung's update server, the same package other sites call the flash file or the software update. It installs with Odin on a Windows PC.
No. Factory Reset Protection is tied to the Google account that was on the phone and survives a firmware flash. Sign in with that account or use the legal options in our FRP guide.