
Samsung Galaxy Note3
The latest firmware for Samsung Galaxy Note3 (SM-N900S) is N900SKSUFNH4 with Android 4.4.2 (KitKat), released on August 16, 2014 for 1 region (CSC). Every official firmware build for SM-N900S, newest first: one row per build with all regions (CSC) that received it.
Each firmware build has its own page at https://samfirm.shop/build/{PDA}, where {PDA} is the build number from the list above. Example: https://samfirm.shop/build/N900SKSUFNH4
All 12 builds in our database run Android 4.4.2 (KitKat). The newest build, N900SKSUFNH4, was released on August 16, 2014. No new build has appeared for 148 months, so regular updates for this model have most likely ended.
Specifications of SM-N900, a regional variant of the same device. Chipset and SIM lines are left out: they can differ by region.

SM-N900V

SM-N910V

SM-N915V

SM-N916S

SM-N920AZW
The newest firmware for SM-N900S runs Android 4.4.2 (KitKat): build N900SKSUFNH4, released on August 16, 2014.
The latest build for SM-N900S, N900SKSUFNH4, was released on August 16, 2014 (12 years ago).
SM-N900S has had no new firmware for 148 months, so regular updates have most likely ended.
Yes, all firmware files for SM-N900S are 100% official, original, and obtained directly from Samsung servers.
To flash SM-N900S, 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-N900S.