M566BXXU5BZB4 – Galaxy M56 5G firmware

Build M566BXXU5BZB4 is a feature update for the Galaxy M56 5G (SM-M566B) on Android 16 (One UI 8). It first appeared on Samsung's servers on Mar 2, 2026 (method) and has reached 1 region so far. It raises the bootloader bit from 4 to 5: once installed, the device no longer accepts firmware with bit 4 or lower, so a downgrade to M566BXXS4BYK2 is blocked. Samsung still serves this file.

Model
SM-M566B
Android
Android 16
Type
Feature
Bootloader bit
5
First released
Mar 2, 2026
Regions
1

Rollout timeline by region

The date each region code (CSC) first received M566BXXU5BZB4, counted from the first release.

CSCRegionReleasedRolloutVersion (PDA/CSC/MODEM)
INSIndiaMar 2, 2026day 0M566BXXU5BZB4/M566BODM5BZB4/M566BXXU5BZB4

Download and release notes

samloader download -m SM-M566B -r INS -v M566BXXU5BZB4/M566BODM5BZB4/M566BXXU5BZB4

Samsung's release notes and security patch level for this update: SM-M566B / INS on doc.samsungmobile.com. What each part of the build number means: decode M566BXXU5BZB4.