Chinese regulatory filings suggest the iPhone 18 Pro Max could ship with one of the largest battery capacity increases in the phone's history, while its smaller sibling, the iPhone 18 Pro, appears to be getting only a marginal bump. The figures come from certification listings spotted by Weibo leaker Digital Chat Station in China's 3C regulatory database, a source that has previously provided accurate early battery data ahead of past iPhone launches.

What the filings show

According to the listings, the iPhone 18 Pro Max's eSIM-only model, the version typically sold in the United States, is rated for a 5,567 mAh battery, up from 5,088 mAh in the iPhone 17 Pro Max. The physical-SIM version, sold in China and other regions, comes in at 5,391 mAh, compared to 4,823 mAh a year earlier. Both figures represent increases of roughly 9 to 12 percent.

17 Pro Max (eSIM) 5,088 mAh
18 Pro Max (eSIM) 5,567 mAh
17 Pro Max (SIM) 4,823 mAh
18 Pro Max (SIM) 5,391 mAh

The standard iPhone 18 Pro tells a different story. Its eSIM model is listed at 4,288 mAh, only slightly above the iPhone 17 Pro's 4,252 mAh, while the physical-SIM version moves from roughly 3,988 mAh to 4,056 mAh. Both changes amount to gains of less than 2 percent, widening the gap between the two Pro models further than in previous generations.

Why it matters beyond capacity

A larger cell isn't the only factor expected to affect battery life. The iPhone 18 Pro lineup is rumored to use Apple's next-generation A20 Pro chip, built on TSMC's 2nm process, along with a new C2 modem outside the US. Both are expected to improve power efficiency, meaning real-world battery life gains could exceed what the raw capacity numbers suggest.

Context: Apple is expected to unveil the iPhone 18 Pro and iPhone 18 Pro Max in September, alongside its first foldable iPhone. Unlike prior years, the standard iPhone 18 is reportedly not part of that lineup and may not arrive until early 2027.

These figures come from unofficial regulatory filings and third-party leakers rather than an Apple announcement. Apple does not publish battery capacities ahead of launch, and final specifications are typically confirmed only through post-release teardowns.

How much bigger is the iPhone 18 Pro Max battery expected to be?

Filings point to roughly a 9 to 12 percent increase over the iPhone 17 Pro Max, depending on the SIM configuration.

Is the iPhone 18 Pro getting the same upgrade?

No. Filings suggest the standard iPhone 18 Pro will see a much smaller increase, under 2 percent over its predecessor.

When will these numbers be confirmed?

Apple typically doesn't confirm battery capacities directly; final numbers are usually verified through teardowns after the iPhones launch, expected this September.