IPhone 18 Pro Max Battery Jumps 568mAh While Standard Pro Stalls

Chinese regulatory filings have surfaced battery figures for two upcoming iPhone models, and the numbers tell different stories depending on which Pro you’re buying. Listings in China’s C3 database put the iPhone 18 Pro Max at 5,391mAh for the Chinese market and 5,567mAh for the U.S. model. The iPhone 18 Pro, by contrast, is listed at 4,056mAh in China and 4,288mAh in the U.S., a much smaller step forward.

The gap between the two models is the real story here. The Pro Max is pulling noticeably further ahead of the standard Pro than it has in recent cycles, while the Pro itself barely moves from its iPhone 17 predecessor.

The capacity difference between Chinese and U.S. versions comes down to physical space. Apple’s eSIM-only design for U.S. models removes the SIM tray, freeing up enough internal room for a slightly larger cell. The filings also include battery model numbers, rated energy figures up to 21.751Wh, and a 4.520V charge limit voltage.

For context on how significant the Pro Max jump is:

• iPhone 17 Pro Max China: 4,823mAh
• iPhone 17 Pro Max U.S.: 5,088mAh
• iPhone 18 Pro Max China: 5,391mAh
• iPhone 18 Pro Max U.S.: 5,567mAh

That’s a roughly 568mAh increase for the U.S. Pro Max, a larger single-generation leap than Apple typically makes on battery capacity.

The bigger battery arrives alongside an expected 2nm A20 Pro chip, which should push efficiency gains on top of the raw capacity increase. Apple is also rumored to add a variable aperture main camera, a smaller Dynamic Island, and a C2 modem for select markets. The iPhone 18 Pro and Pro Max are expected in September, launching at the same time as Apple’s first foldable device.