A366USQS9CZG2 – Galaxy A36 5G firmware
Build A366USQS9CZG2 is a security update for the Galaxy A36 5G (SM-A366U)
on Android 16 (One UI 8). It first appeared on Samsung's servers on Aug 3, 2026 (method) and has reached
9 regions so far. It raises the bootloader bit from 8 to 9: once installed, the device no longer accepts firmware with bit 8 or lower, so a downgrade to A366USQS8CZF1 is blocked. Samsung still serves this file.
- Model
- SM-A366U
- Android
- Android 16
- Type
- Security
- Bootloader bit
- 9
- First released
- Aug 3, 2026
- Regions
- 9
Rollout timeline by region
The date each region code (CSC) first received A366USQS9CZG2, counted from the first release.
| CSC | Region | Released | Rollout | Version (PDA/CSC/MODEM) |
|---|---|---|---|---|
ATT | USA (AT&T) | Aug 3, 2026 | day 0 | A366USQS9CZG2/A366UOYN9CZG2/A366USQS9CZG2 |
AIO | USA (Cricket) | Aug 4, 2026 | +1 day | A366USQS9CZG2/A366UOYN9CZG2/A366USQS9CZG2 |
CCT | USA (Comcast) | Aug 4, 2026 | +1 day | A366USQS9CZG2/A366UOYN9CZG2/A366USQS9CZG2 |
TMB | USA (T-Mobile) | Aug 4, 2026 | +1 day | A366USQS9CZG2/A366UOYN9CZG2/A366USQS9CZG2 |
TMK | USA (MetroPCS) | Aug 4, 2026 | +1 day | A366USQS9CZG2/A366UOYN9CZG2/A366USQS9CZG2 |
VZW | USA (Verizon) | Aug 4, 2026 | +1 day | A366USQS9CZG2/A366UOYN9CZG2/A366USQS9CZG2 |
DSH | USA | Aug 7, 2026 | +4 days | A366USQS9CZG2/A366UOYN9CZG2/A366USQS9CZG2 |
DSA | USA | Aug 7, 2026 | +4 days | A366USQS9CZG2/A366UOYN9CZG2/A366USQS9CZG2 |
USC | USA (US Cellular) | Aug 9, 2026 | +6 days | A366USQS9CZG2/A366UOYN9CZG2/A366USQS9CZG2 |
Download and release notes
samloader download -m SM-A366U -r ATT -v A366USQS9CZG2/A366UOYN9CZG2/A366USQS9CZG2Samsung's release notes and security patch level for this update: SM-A366U / ATT on doc.samsungmobile.com. What each part of the build number means: decode A366USQS9CZG2.