Samsung Is Already Testing One UI 9.5 — And It Confirms a Four-Phone S27 Lineup

Samsung moves fast on software. Faster than most people realize. Internal firmware testing for the entire Galaxy S27 series is now officially underway, with all four models spotted on Samsung's US test servers running early One UI 9.5 builds.

Four models. That's the key detail here.

The Galaxy S27 lineup will include the S27, S27+, S27 Pro, and S27 Ultra — four phones instead of the usual three. The Pro slot is brand new. The S27 Pro is expected to be notably more compact than the Ultra, with a display of just under 6.5 inches. No S Pen support is expected on that one. Think of it as the option between the base model and the Ultra — not a slight bump up, but a genuinely different size class.

The first One UI 9.5 firmware — build number S958USQU0AZH3 — was spotted on Samsung's servers for the US Galaxy S27 Ultra. This build landed on the software server nearly six months before the phone's expected public debut. That's early, even for Samsung. It also means the development timeline is ahead of schedule compared to previous years.

One UI 9.5 will be based on Android 17 — the same Android version as One UI 9.0. So it's not a new Android generation. It's Samsung's mid-cycle refinement, the same way One UI 8.5 shipped with the S26 series. Galaxy AI will remain front and center, with further development expected across Now Bar, Now Brief, and Bixby.

One feature worth noting: the Privacy Display introduced on the S26 Ultra is now rumored to extend across the entire S27 lineup — base model included. That's a meaningful trickle-down if it holds.

Not yet. A public One UI 9.5 beta program isn't expected to open until around November, with the Galaxy S26 series first in line. The S27 itself is still months out. Samsung is expected to announce the Galaxy S27 series in February 2027.