Samsung recently launched the Galaxy S25 Ultra with several notable upgrades. One standout feature is faster wireless charging when using a Qi2-compatible magnetic case. The phone also supports reverse wireless charging, allowing you to power up your Galaxy Watch or Buds by placing them on its back. But can it charge the Galaxy Watch Ultra, Samsung’s most powerful smartwatch yet? Let’s find out.
Galaxy S25 Ultra has reverse wireless charging, but does it support all wearables?
Reverse wireless charging, aka Wireless PowerShare, is a useful feature found on flagship Galaxy smartphones. It allows users to charge their wearable devices wirelessly through the phone’s wireless charging coil. It can be handy when your wearable runs out of power and you cannot immediately put it to charge. This feature has been available on Galaxy flagships for so long, and the Galaxy S25 series keeps it.
However, Samsung made some changes to its watches last year. The Galaxy Watch Ultra and Galaxy Watch 7 feature a redesigned BioActive sensor for more accurate health tracking. This design change repositioned the internal wireless charging coil deeper within the watch, preventing it from wirelessly drawing enough power from Galaxy phones.
Samsung made this trade-off to improve health tracking, and we aren’t complaining. The company even advises against using older charging pucks with the Galaxy Watch Ultra or Watch 7, as they can’t deliver full-speed charging for the new watches. Thankfully, it seems to have worked some magic with the Galaxy S25 Ultra.
Despite a hardware limitation on the watch itself, the new flagship can reverse charge your Galaxy Watch Ultra or Watch 7 wirelessly. It is not as efficient as the Galaxy Watch 6 or older models, though. We tested reverse charging the Watch Ultra on our Galaxy S25 Ultra, and it charged only when we carefully held the watch on the phone’s back.
There is a workaround if you have the charging puck nearby. You can simply insert the cable on your phone’s USB-C port and the watch will draw power from the phone to charge itself. You don’t need to find an adapter or power socket to charge your watch. This method may not be as convenient as reverse wireless charging, but it gets the job done in emergencies.
