IPhone 18 Pro Max Battery Jumps to 5,567mAh in U.S. Model

Regulatory filings in China’s C3 database, spotted by leaker Digital Chat Station on Weibo, put the iPhone 18 Pro Max battery at 5,391mAh for the Chinese model and 5,567mAh for the U.S. version. That U.S. figure is somewhat higher than an earlier leak that pegged the eSIM model at 5,425mAh, though both point in the same direction: a meaningful jump from the iPhone 17 Pro Max’s 5,088mAh U.S. capacity.

The Pro tells a different story. Its capacity rises from 3,988mAh to 4,056mAh in China and from 4,252mAh to 4,288mAh in the U.S., increases of 68mAh and 36mAh respectively. After the iPhone 17 Pro added several hundred milliampere-hours over its predecessor, the 18 Pro’s modest battery bump looks like Apple holding the line rather than pushing it.

The gap between Chinese and U.S. capacities exists for a structural reason. Apple has shipped U.S. iPhones without a physical SIM tray since the iPhone 14 lineup, and the space freed by going eSIM-only allows a slightly larger cell to fit inside the chassis. The Chinese models retain the tray, which is why their numbers consistently run lower.

What the filings actually show

The certification documents cover four battery model numbers across the two devices and list rated energy figures of up to 21.751Wh, a 4.520V charge limit voltage, and validity dates running through May or June 2031. The filings do not name the devices directly as iPhone 18 Pro models, though the numbers align with figures Digital Chat Station published in a separate June report.

Digital Chat Station also suggested that pairing a 5,391mAh cell with the 2nm A20 Pro chip could produce a noticeable battery life improvement, where efficiency gains from the chip do as much work as the added capacity. The iPhone 18 Pro models are also rumored to include a variable aperture main camera and a smaller Dynamic Island, and are expected to launch in September alongside Apple’s first foldable iPhone.