First One UI 8 beta build for the Samsung Galaxy S25 Ultra appears on test servers

The Samsung Galaxy S25, S25+ and S25 Ultra may have launched with One UI 7, but when it comes to One UI 8 they will have to wait for an over-the-air update like all the other Galaxys. This could come sooner than expected, though.
The first One UI 8 beta build for the Galaxy S25 Ultra has been spotted by Tarun Vats. The new firmware is S938BXXU3ZYEA / S938BOXM3ZYEA / S938BXXU3BYEA.
Looking back a generation, the Samsung Galaxy S24 Ultra got a One UI 7 test build back in May 2024. A number of delays pushed the stable rollout to April of this year. That was a major update, however, that significantly reworked the One UI parts of the firmware, not just the base Android OS. One UI 8 will reportedly build on 7 and should be a simpler update.
First One UI 8 beta build for Galaxy S25 Ultra appears on test servers
According to Vats, the first public One UI 8 beta for the Galaxy S25 series will be out in mid-June. How that beta performs will be indicative of how long we will have to wait for a stable release.
A video demo and some screenshots from early One UI 8 builds have already leaked. Below is a fresh video that shows off Samsung"s progress in polishing the transition animations in One UI:
Latest One Ui 8 Build ZYEA animations: pic.twitter.com/upzRNpef5b
— IposDev (@DevOfIpos) May 8, 2025
The first phones that will run the new software out of the box will be the Galaxy Z Fold7 and Z Flip7, which are expected in late July or early August.
Interestingly, previous Galaxy foldables have launched with the same major One UI version as that year’s Galaxy S series (just with a minor version update). This suggests that One UI 8 is further along its development than 7 was at the same time last year.
Samsung is already looking ahead too, with leaks suggesting that it’s working on One UI 8.5 for the future Galaxy S26 series.