A556BXXSHDZH6 – Galaxy A55 5G firmware

Build A556BXXSHDZH6 is a security update for the Galaxy A55 5G (SM-A556B) on Android 16 (One UI 8). It first appeared on Samsung's servers on Sep 2, 2026 (method) and has reached 16 regions so far. It raises the bootloader bit from 16 to 17: once installed, the device no longer accepts firmware with bit 16 or lower, so a downgrade to A556BXXSGDZG2 is blocked. Samsung still serves this file.

Model
SM-A556B
Android
Android 16
Type
Security
Bootloader bit
17
First released
Sep 2, 2026
Regions
16

Rollout timeline by region

The date each region code (CSC) first received A556BXXSHDZH6, counted from the first release.

CSCRegionReleasedRolloutVersion (PDA/CSC/MODEM)
BOGFrance (Bouygues)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
EUXEurope (Multi-CSC)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
EUYEurope (Multi-CSC)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
EVRUnited Kingdom (EE)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
MEOPortugal (MEO)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
MOBAustria (A1)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
MOTSlovenia (Telekom)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
MSRSerbiaSep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
O2CCzech Republic (O2)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
PLSPoland (Plus)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
PRTPoland (Play)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
SFRFrance (SFR)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
SIMSlovenia (A1)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
SWCSwitzerlandSep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
TOPSerbia/MontenegroSep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6
VIPCroatia (A1)Sep 2, 2026day 0A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6

Download and release notes

samloader download -m SM-A556B -r EUX -v A556BXXSHDZH6/A556BOXMHDZH6/A556BXXSHDZH6

Samsung's release notes and security patch level for this update: SM-A556B / EUX on doc.samsungmobile.com. What each part of the build number means: decode A556BXXSHDZH6.