Samsung is pushing the fifth One UI 8.5 beta to Galaxy S25 series testers, signaling that the software destined for the upcoming Galaxy S26 lineup is entering its final stretch of polishing. The new build, identified by a firmware suffix ending in ZZAN, prioritizes stability and reliability as the company tightens screws ahead of the next flagship launch.
What’s included in One UI 8.5 Beta 5 release
This release lands with a small download size—about 553MB for most users—and a concise changelog. The headline items: an updated Bixby version and the latest Android security patch level. Samsung isn’t touting flashy additions, and early tester feedback hasn’t surfaced visible new features, which typically suggests regression fixes, performance refinement, and under-the-hood cleanup.

Notably, the previous beta introduced a modernized voicemail experience for select regions, so it’s no surprise that Beta 5 leans conservative. Late-cycle beta drops often act as “stability gates,” squashing edge-case crashes and tightening system services so the stable build can be certified for carrier networks and global markets.
Where One UI 8.5 Beta 5 is rolling out first
Community spotters, including Tarun Vats on X, report that the update is live for Galaxy S25 testers in South Korea, India, Germany, and the UK, with more regions expected to follow. Samsung’s beta program typically staggers availability to monitor crash analytics in waves before expanding to North America and other markets.
Participants can check for the update via Settings > Software update, and confirm the ZZAN firmware tag once installed. As always with test builds, a full backup is recommended; while day-to-day stability has improved across recent betas, isolated compatibility issues with banking apps, accessories, or launcher tweaks can still appear.
Why this beta matters for the upcoming Galaxy S26 series
One UI 8.5 is widely expected to ship on the Galaxy S26 series out of the box, making the S25 beta track the de facto proving ground. The arrival of a fifth beta suggests a feature freeze is largely in place. Historically, Samsung closes flagship beta programs after a handful of late-cycle builds—often in the 4–8 range—once bug metrics drop below internal thresholds and carrier test suites pass.
The updated Bixby component is also telling. As Samsung leans harder into on-device intelligence, background services like voice, offline processing, and cross-app tasking need to be rock-solid at launch. Tightening those pieces now reduces risk when new hardware and features debut together.

What testers should expect in One UI 8.5 Beta 5
Don’t expect splashy UI changes in this drop. Watch instead for smoother animations, fewer app restarts, improved battery consistency across mixed 5G and Wi‑Fi use, and better camera handoffs between lenses—areas that commonly see late-cycle tuning even when not explicitly called out in notes.
If you rely on DeX, enterprise VPNs, or complex Bluetooth stacks (multipoint headphones, watches, and car systems together), consider filing logs through Samsung Members if you spot hiccups. Those reports feed directly into engineering dashboards and often determine whether a release candidate graduates to stable or needs another spin.
The bigger picture on updates and Samsung’s release pace
Samsung’s recent flagships come with extended software support, and the company has pushed faster security patch cadence than most Android peers. Industry trackers such as Counterpoint Research and IDC have noted Samsung’s aggressive update posture as a competitiveness lever, particularly in premium tiers where ownership cycles are longer.
That context helps explain the measured pace here: fewer headline features late in beta, more validation around reliability, and incremental service updates like Bixby to align with what will ship on fresh hardware. If the pattern holds, the next signpost to watch is either a release candidate build for S25 testers or the first stable One UI 8.5 firmware arriving in early markets as carriers sign off.
For now, Beta 5 reads like a confidence pass—light on novelty, heavy on the kind of polish that makes a new phone and a new software version feel cohesive on day one.
