Samsung's Galaxy S27 Ultra is getting a battery upgrade that's both overdue and genuinely meaningful. According to regulatory filings spotted in China's 3C certification database, the S27 Ultra will pack a 5,700mAh battery—a 700mAh jump over the 5,000mAh cell Samsung has shipped in every Ultra model since the Galaxy S21 Ultra in 2021.
That's five straight years of the same battery capacity across flagship hardware that got bigger displays, faster processors, and more power-hungry AI features. The S27 Ultra's bump to 5,700mAh isn't radical by Chinese OEM standards, but it's the first time Samsung has acknowledged that 5,000mAh wasn't cutting it anymore.
The Galaxy S27 Pro gets similar treatment, with a leaked 5,200mAh battery that also surpasses last year's Ultra flagship. Both phones share the same 60W wired charging spec, matching the S26 Ultra exactly. That's where the good news ends.
60W is fine for most people, but it's also the same ceiling Samsung has maintained while Chinese competitors routinely ship 100W or faster charging. The capacity gap narrowed; the charging speed gap did not. If you wanted Samsung to finally match OnePlus or Xiaomi on raw wattage, these leaks confirm that's not happening in this generation.
The model numbers in question, SM-S957 and SM-S958, haven't been officially named by Samsung, but multiple outlets have consistently mapped them to the S27 Pro and S27 Ultra. The battery figures represent rated capacity, which typically translates to slightly higher advertised numbers once Samsung rounds for marketing. The phones won't launch until early 2027, so consider everything here preliminary until Samsung steps up with official specs.
Still, if battery endurance drives your upgrade decision, this is the most encouraging leak Samsung has produced in years. The company finally moved the needle on capacity after half a decade of standing still. Whether that's enough to justify waiting for the S27 over buying a discounted S26 depends entirely on whether an extra 700mAh matters more to you than whatever deal you can grab today.
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