iPhone 18 Pro Max Leak Reveals Biggest iPhone Battery Ever, and US Buyers Get More Than China Does

Apple's iPhone 18 Pro Max is on course to carry the biggest battery ever fitted to an iPhone, and US buyers will get more capacity than customers in China. Filings in China's 3C regulatory database list a 5,567mAh cell for the American model, first shared by Weibo leaker Digital Chat Station on Monday.

The timing matters because September upgrade decisions start now, and the numbers change the calculation. The Pro Max gains nearly 10% over last year's model while the smaller iPhone 18 Pro barely moves at all. Battery life is the upgrade ordinary buyers actually notice, and the split between the two Pro models could decide which one is worth the money.

Apple is expected to reveal the iPhone 18 Pro, the iPhone 18 Pro Max, and its first foldable iPhone in September 2026, though the foldable may ship later.

Why US Buyers Get the Bigger Battery

The regional split comes down to the SIM tray. American iPhones dropped the physical slot in 2022 in favour of the embedded SIM (eSIM), freeing internal space that Apple now fills with battery. The filings list the US Pro Max at 5,567mAh against 5,391mAh for the Chinese variant, which still needs a physical SIM.

The same pattern holds on the smaller phone. The US iPhone 18 Pro is listed at 4,288mAh while the Chinese version carries 4,056mAh.

Pro Max Gains 10% While Pro Gets Under 1%

The year-over-year gap is where the leak gets interesting for buyers. Last year's iPhone 17 Pro Max shipped with a 5,088mAh battery in the US, so the new cell represents a 9.4% jump. The iPhone 18 Pro climbs from 4,252mAh to 4,288mAh, a rise of less than 1%.

Even Digital Chat Station said the figures need further verification because the gains are so large. Chinese regulatory filings have a strong track record, though, and the same database accurately revealed iPhone 17 Pro capacities before launch in 2025.

Earlier reports also suggested the iPhone 18 Pro Max will be thicker and heavier than the Pro, which would make room for the larger cell.

Closing the Gap With Android Flagships

A 5,567mAh battery would put the Pro Max level with, and in some cases ahead of, flagship Android phones from Samsung, OnePlus, and Xiaomi, which now routinely ship above 5,000mAh. Apple has traditionally topped battery charts using smaller cells paired with efficient chips, so a bigger battery combined with its next-generation A-series processor could deliver a real jump in screen time.

No Standard iPhone 18 This Autumn

The leak carries a second consequence for budget shoppers. Apple isn't releasing a standard iPhone 18 this autumn. The base model and the cheaper iPhone 18e are being held until spring 2027 under a split launch calendar, a plan corroborated by analyst Ming-Chi Kuo and Nikkei. Largan Precision chairman Lin En-ping added weight to those reports in June, telling shareholders a major US customer had pushed a new model to the first quarter of 2027.

That leaves September buyers choosing between two Pro models and a foldable expected to cost around $2,000 (£1,497). Anyone who usually buys the cheapest new iPhone faces a simple choice. Pay Pro money now or wait six months.

Apple hasn't confirmed the figures and doesn't comment on unreleased products. The full picture arrives at the September event, but if the filings hold, battery life will be the clearest reason yet to choose the Pro Max over the Pro.