Samsung Galaxy S26 Series Starts Early One UI 9.5 Testing While One UI 9 is Still in Beta

It’s common knowledge at this point. Samsung Galaxy S26 series has been a subject of One UI 9 beta testing since May. The stable update hasn’t even come out yet, but it seems they have already begun the One UI 9.5 firmware development for the series. This will be the mid-year refresh of the stable One UI 9 on the Galaxy S26 series.

A leaker on X has found a new firmware build number on Samsung's test server, and the source is confident that it’s actually a One UI 9.5 test software for the Galaxy S26 series. Apparently, the build number ends with CZH1.

The leaker’s word is all we have, though he is a known source for these kinds of predictions and rumors. His track record is nothing to scoff at, so we are also giving him the benefit of the doubt here. It would seem that Samsung may actually have One UI 9.5 under testing for their Galaxy S26. 

By the way, this is happening way too soon. One UI 8.5 test build development was nowhere near this window last year for the Galaxy S25 group. Of course, if they really have started One UI 9.5 x Galaxy S26 testing this early, it would be logical to assume that the actual update might also come out sooner. 

It’s Samsung we are talking about here, a company better known for its software support, so obviously this is all possible. Not the stable update, but we can at least expect One UI 9.5 beta before we hit December. That’s when they started Galaxy S25’s One UI 8.5 beta shipment last year. 

Obviously, these are all future plans. What people are looking at right now is the stable One UI 9. And it’s still in beta phase. There are reports that at least one more beta update is left before they can make the One UI 9 update official on the Galaxy S26 series. And Samsung would then think of putting the same update on the Galaxy S25 trio. Keep watching the news for more.