S918U1UES8FZF5 – Galaxy S23 Ultra firmware
Build S918U1UES8FZF5 is a security update for the Galaxy S23 Ultra (SM-S918U1)
on Android 16 (One UI 8). It first appeared on Samsung's servers on Jun 29, 2026 (method) and has reached
14 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 S918U1UES7FZE3 is blocked. Samsung still serves this file.
- Model
- SM-S918U1
- Android
- Android 16
- Type
- Security
- Bootloader bit
- 8
- First released
- Jun 29, 2026
- Regions
- 14
Rollout timeline by region
The date each region code (CSC) first received S918U1UES8FZF5, counted from the first release.
| CSC | Region | Released | Rollout | Version (PDA/CSC/MODEM) |
|---|---|---|---|---|
ACG | USA (C Spire) | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
AIO | USA (Cricket) | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
ATT | USA (AT&T) | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
CCT | USA (Comcast) | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
DSA | USA | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
DSH | USA | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
LRA | USA (Bluegrass) | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
TFN | USA (TracFone) | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
TMB | USA (T-Mobile) | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
TMK | USA (MetroPCS) | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
USC | USA (US Cellular) | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
VZW | USA (Verizon) | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
XAA | USA (unlocked) | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
XAR | USA (Cellular South) | Jun 29, 2026 | day 0 | S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5 |
Download and release notes
samloader download -m SM-S918U1 -r XAA -v S918U1UES8FZF5/S918U1OYM8FZF5/S918U1UES8FZF5Samsung's release notes and security patch level for this update: SM-S918U1 / XAA on doc.samsungmobile.com. What each part of the build number means: decode S918U1UES8FZF5.