A566U1UES8CZF6 – Galaxy A56 5G firmware

Build A566U1UES8CZF6 is a security update for the Galaxy A56 5G (SM-A566U1) on Android 16 (One UI 8). It first appeared on Samsung's servers on Jun 30, 2026 (method) and has reached 11 regions so far. It raises the bootloader bit from 7 to 8: once installed, the device no longer accepts firmware with bit 7 or lower, so a downgrade to A566U1UES7CZE5 is blocked. Samsung still serves this file.

Model
SM-A566U1
Android
Android 16
Type
Security
Bootloader bit
8
First released
Jun 30, 2026
Regions
11

Rollout timeline by region

The date each region code (CSC) first received A566U1UES8CZF6, counted from the first release.

CSCRegionReleasedRolloutVersion (PDA/CSC/MODEM)
ACGUSA (C Spire)Jun 30, 2026day 0A566U1UES8CZF6/A566U1OYM8CZF6/A566U1UES8CZF6
AIOUSA (Cricket)Jun 30, 2026day 0A566U1UES8CZF6/A566U1OYM8CZF6/A566U1UES8CZF6
ATTUSA (AT&T)Jun 30, 2026day 0A566U1UES8CZF6/A566U1OYM8CZF6/A566U1UES8CZF6
CCTUSA (Comcast)Jun 30, 2026day 0A566U1UES8CZF6/A566U1OYM8CZF6/A566U1UES8CZF6
LRAUSA (Bluegrass)Jun 30, 2026day 0A566U1UES8CZF6/A566U1OYM8CZF6/A566U1UES8CZF6
TMBUSA (T-Mobile)Jun 30, 2026day 0A566U1UES8CZF6/A566U1OYM8CZF6/A566U1UES8CZF6
TMKUSA (MetroPCS)Jun 30, 2026day 0A566U1UES8CZF6/A566U1OYM8CZF6/A566U1UES8CZF6
USCUSA (US Cellular)Jun 30, 2026day 0A566U1UES8CZF6/A566U1OYM8CZF6/A566U1UES8CZF6
VZWUSA (Verizon)Jun 30, 2026day 0A566U1UES8CZF6/A566U1OYM8CZF6/A566U1UES8CZF6
XAAUSA (unlocked)Jun 30, 2026day 0A566U1UES8CZF6/A566U1OYM8CZF6/A566U1UES8CZF6
XARUSA (Cellular South)Jun 30, 2026day 0A566U1UES8CZF6/A566U1OYM8CZF6/A566U1UES8CZF6

Download and release notes

samloader download -m SM-A566U1 -r XAA -v A566U1UES8CZF6/A566U1OYM8CZF6/A566U1UES8CZF6

Samsung's release notes and security patch level for this update: SM-A566U1 / XAA on doc.samsungmobile.com. What each part of the build number means: decode A566U1UES8CZF6.