A266USQSACZH3 – Galaxy A26 5G firmware
Build A266USQSACZH3 is a security update for the Galaxy A26 5G (SM-A266U)
on Android 16 (One UI 8). It first appeared on Samsung's servers on Sep 8, 2026 (method) and has reached
2 regions so far. It raises the bootloader bit from 9 to 10: once installed, the device no longer accepts firmware with bit 9 or lower, so a downgrade to A266USQS9CZG2 is blocked. Samsung still serves this file.
- Model
- SM-A266U
- Android
- Android 16
- Type
- Security
- Bootloader bit
- 10
- First released
- Sep 8, 2026
- Regions
- 2
Rollout timeline by region
The date each region code (CSC) first received A266USQSACZH3, counted from the first release.
| CSC | Region | Released | Rollout | Version (PDA/CSC/MODEM) |
|---|---|---|---|---|
USC | USA (US Cellular) | Sep 8, 2026 | day 0 | A266USQSACZH3/A266UOYNACZH3/A266USQSACZH3 |
CCT | USA (Comcast) | Sep 10, 2026 | +2 days | A266USQSACZH3/A266UOYNACZH3/A266USQSACZH3 |
Download and release notes
samloader download -m SM-A266U -r USC -v A266USQSACZH3/A266UOYNACZH3/A266USQSACZH3Samsung's release notes and security patch level for this update: SM-A266U / USC on doc.samsungmobile.com. What each part of the build number means: decode A266USQSACZH3.