Samsung has quietly begun software development for its Galaxy S26 flagship, despite still being months away from its expected launch in early 2026. A test firmware for the Galaxy S26 Ultra has been spotted on Samsung's internal servers, suggesting that initial testing has already begun.

X-based @Koram_Akhilesh was the first to spot the test build, which is codenamed S948USQU0AYG8. While not many details have been revealed, it's a clear sign that Samsung is focusing on fine-tuning new One UI features and improving stability for its next-generation Galaxy S series. As per its annual roadmap, the Galaxy S26 is likely to ship with Android 16 with One UI 8.5.

According to recent leaks, the Galaxy S26 series will include three models: Galaxy S26, S26 Edge, and S26 Ultra. Unlike previous years, Samsung may no longer have a “Plus” version and replace it with the Edge line, with a configuration and size between the standard and Ultra versions. This is an adjustment from the strategy applied to the Galaxy S25 series this year.

Based on the firmware code, the Galaxy S26 Ultra will carry the model number SM-S948. Meanwhile, the S26 Edge version could be SM-S947 or SM-S946 (which was the code for the Plus line before). The standard version is predicted to be SM-S941. With the FE version, the Galaxy S25 FE uses the code SM-S731, so it is very likely that the S26 FE will follow with the code SM-S741.

The Galaxy S26 Ultra is expected to be officially launched early next year, possibly in February as usual. Meanwhile, Samsung is continuing to widely roll out One UI 8 to existing devices, after the new interface debuted with the Galaxy Z Fold 7, Flip 7, and Flip 7 FE. More details about the Galaxy S26 will gradually be revealed in the coming months.