G990U1UESMIZB2 – Galaxy S21 FE 5G firmware

Build G990U1UESMIZB2 is a security update for the Galaxy S21 FE 5G (SM-G990U1) on Android 16 (One UI 8). It first appeared on Samsung's servers on Mar 15, 2026 (method) and has reached 14 regions so far. It raises the bootloader bit from 21 to 22: once installed, the device no longer accepts firmware with bit 21 or lower, so a downgrade to G990U1UESLIZA1 is blocked. Samsung still serves this file.

Model
SM-G990U1
Android
Android 16
Type
Security
Bootloader bit
22
First released
Mar 15, 2026
Regions
14

Rollout timeline by region

The date each region code (CSC) first received G990U1UESMIZB2, counted from the first release.

CSCRegionReleasedRolloutVersion (PDA/CSC/MODEM)
ACGUSA (C Spire)Mar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
AIOUSA (Cricket)Mar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
ATTUSA (AT&T)Mar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
CCTUSA (Comcast)Mar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
DSAUSAMar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
DSHUSAMar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
LRAUSA (Bluegrass)Mar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
TMBUSA (T-Mobile)Mar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
TMKUSA (MetroPCS)Mar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
USCUSA (US Cellular)Mar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
VZWUSA (Verizon)Mar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
XAAUSA (unlocked)Mar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
XARUSA (Cellular South)Mar 15, 2026day 0G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2
TFNUSA (TracFone)Mar 16, 2026+1 dayG990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2

Download and release notes

samloader download -m SM-G990U1 -r XAA -v G990U1UESMIZB2/G990U1OYMMIZB2/G990U1UESMIZB2

Samsung's release notes and security patch level for this update: SM-G990U1 / XAA on doc.samsungmobile.com. What each part of the build number means: decode G990U1UESMIZB2.