Galaxy S21 Series Receives May 2025 Security Update with Android 15 Enhancements
Samsung boosts stability and security in latest One UI 7 patch for S21 lineup
Samsung rolls out fresh software update for Galaxy S21 series
Samsung has begun rolling out the May 2025 security update for its Galaxy S21, S21+, and S21 Ultra smartphones. This update, based on Android 15, improves system security, stability, and overall device performance under One UI 7.
- The rollout has started in Asian regions, including Vietnam, and will expand to other markets in the coming days.
- The update package is approximately 300MB in size and is now available via Settings > Software Update > Download and install.
Software version details
The update comes with the following One UI build numbers, allowing users to verify their specific update:
- Galaxy S21: G991BXXSFHYE1
- Galaxy S21 Plus: G996BXXSFHYE1
- Galaxy S21 Ultra: G998BXXSFHYE1
This is the first Android 15-based monthly update for the Galaxy S21 series, improving the One UI 7 experience for eligible users.
What’s new in the May 2025 update?
The update includes the latest Android security patch, fixing known vulnerabilities and improving system performance.
- It addresses minor bugs from previous firmware versions and enhances some functions for smoother operation.
- Users can expect improved device reliability, reduced system lag, and better background task management.
One UI 8 Beta is coming—but not for S21 series
While Samsung is internally testing One UI 8, the Galaxy S21, S21+, and S21 Ultra are not eligible for the upcoming Android 16-based update.
- These models have completed their Android OS update cycle with One UI 7.
- However, the Galaxy S21 FE variant will be part of the next major upgrade cycle and may soon join the One UI 8 Beta program.
