IPhone 18 Pro Max Battery Grows 337 mAh in eSIM-Only Model

A leak circulating on social media, reported by Macworld, puts the iPhone 18 Pro Max battery at 5,425 mAh for the eSIM-only model and 5,235 mAh for the physical SIM version. Those figures represent increases of 337 mAh and 412 mAh respectively over the equivalent iPhone 17 Pro Max configurations.

The gap between the two variants is not arbitrary. Removing the physical SIM tray frees up internal space, and Apple redirects that room into a larger cell. The same dynamic is playing out with the iPhone 18 Pro, where the battery bump is measurably larger in markets that get eSIM-only models than in regions that retain a Nano SIM slot.

On the credibility of the numbers

Macworld flags the source trail as thin, noting the leak originated from social media accounts without a strong public track record. Earlier, separate rumors had also pointed toward a larger battery in the iPhone 18 Pro Max, which at least means these figures are not appearing in a vacuum.

Apple is also expected to pair the new chassis with an A20 Pro chip, which should bring efficiency improvements on top of the raw capacity increase. That combination matters more than either factor alone, since a bigger battery in a less efficient phone does not automatically translate to better screen-on time. Potential buyers should also keep in mind that modem choice by region could still affect real-world battery performance in ways the mAh figure does not capture.

The iPhone 18 Pro Max is expected to launch alongside what Apple watchers believe will be a foldable iPhone debut in September, making the fall lineup unusually crowded at the top end. How charging infrastructure keeps pace with larger batteries across that lineup is a separate question the rumor cycle has not fully answered yet.