F966U1UESDCZJ1 – Galaxy Z Fold7 firmware
Build F966U1UESDCZJ1 is a security update for the Galaxy Z Fold7 (SM-F966U1)
on Android 17 (One UI 9). It first appeared on Samsung's servers on Oct 21, 2026 (method) and has reached
14 regions so far. It raises the bootloader bit from 12 to 13: once installed, the device no longer accepts firmware with bit 12 or lower, so a downgrade to F966U1UEUCCZIH is blocked. Samsung still serves this file.
- Model
- SM-F966U1
- Android
- Android 17
- Type
- Security
- Bootloader bit
- 13
- First released
- Oct 21, 2026
- Regions
- 14
Rollout timeline by region
The date each region code (CSC) first received F966U1UESDCZJ1, counted from the first release.
| CSC | Region | Released | Rollout | Version (PDA/CSC/MODEM) |
|---|---|---|---|---|
ACG | USA (C Spire) | Oct 21, 2026 | day 0 | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
AIO | USA (Cricket) | Oct 21, 2026 | day 0 | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
ATT | USA (AT&T) | Oct 21, 2026 | day 0 | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
CCT | USA (Comcast) | Oct 21, 2026 | day 0 | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
LRA | USA (Bluegrass) | Oct 21, 2026 | day 0 | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
TFN | USA (TracFone) | Oct 21, 2026 | day 0 | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
VZW | USA (Verizon) | Oct 21, 2026 | day 0 | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
XAR | USA (Cellular South) | Oct 21, 2026 | day 0 | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
DSA | USA | Nov 5, 2026 | +15 days | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
DSH | USA | Nov 5, 2026 | +15 days | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
TMB | USA (T-Mobile) | Nov 5, 2026 | +15 days | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
TMK | USA (MetroPCS) | Nov 5, 2026 | +15 days | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
USC | USA (US Cellular) | Nov 5, 2026 | +15 days | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
XAA | USA (unlocked) | Nov 5, 2026 | +15 days | F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1 |
Download and release notes
samloader download -m SM-F966U1 -r XAA -v F966U1UESDCZJ1/F966U1OYMDCZJ1/F966U1UESDCZJ1Samsung's release notes and security patch level for this update: SM-F966U1 / XAA on doc.samsungmobile.com. What each part of the build number means: decode F966U1UESDCZJ1.