Samsung may not have boosted the Galaxy S25 Ultra‘s charging speed on paper, but it still charges slightly faster than its predecessor. In our tests, the new flagship consistently charged quicker than the S24 Ultra, even though both officially support 45W wired charging. This is likely due to its 15V/3A charging profile.
Galaxy S25 Ultra charges in under an hour — here’s the science
While both the Galaxy S25 Ultra are S24 Ultra are rated to charge at up to 45W, the new model supports a 15V/3A charging profile alongside 9V/2.77A. Last year’s flagship charges at 11V/4.05A or 9V/2.77A — all of these charging profiles convert to 45W of power. However, higher voltage has a slight advantage. It reduces power loss in transmission/cable, potentially increasing the charging speed.
This advantage is likely coming into play for the Galaxy S25 Ultra, helping it charge faster. In our tests, the device drew up to 14V of voltage, charging consistently at over 40W for several minutes. The S24 Ultra couldn’t draw more than 9V of voltage with the same USB-C cable and charging adapter, though it did charge at an identical speed for a while.
In practice, the Galaxy S25 Ultra charged fully from 0 in just under an hour (59 minutes and a few seconds). The Galaxy S24 Ultra, on the other hand, took about an hour and six minutes for a full charge. It may not be a huge difference, but still something to note. There may be other factors helping the new model charge faster, but the gist is that it does charge faster than the 2024 model.
The Galaxy S25 Ultra also appears to have a solid battery life, much better than the S24 Ultra (both pack a 5,000mAh battery). We are still evaluating the new Samsung flagship’s everyday performance and battery life, but the device has impressed us in the first few days. Stay tuned for our detailed review later this month.
