iPhone 18 Pro Max battery upgrade could make it Apple’s heaviest phone

Apple’s upcoming iPhone 18 Pro Max could tip the scales at roughly 240 grams, driven by a battery that is about 500 mAh larger than the current model, according to regulatory filings and leaker reports [2]. The added weight and thickness raise questions about how Apple balances longer battery life against the comfort expectations of its flagship‑size users.

Battery size drives the design shift

Chinese regulatory filings reveal a battery capacity of 5,567 mAh for the U.S. market and 5,391 mAh for China, representing an increase of nearly 500 mAh over the iPhone 17 Pro Max’s 5,067 mAh unit [2]. Leaker Ice Universe translates the larger cell into a projected device thickness of about 9 mm and a weight of 240 g, up from the 8.75 mm, 233 g iPhone 17 Pro Max [1][2]. The modest 0.25 mm thickening and 7‑gram weight gain are small on paper but could be perceptible on a device already at the upper end of size and heft.

How the iPhone 18 Pro Max stacks up

Historically, Apple has trimmed weight by moving from stainless steel to titanium on the iPhone 15 Pro line and then to aluminum on the iPhone 17 Pro models [2]. The new stainless‑steel vapor‑chamber cooling system reported for the iPhone 18 Pro Max may offset those gains, adding further mass [2]. At 240 g, the phone would tie the iPhone 14 Pro Max, which has held the title of Apple’s heaviest phone since its launch [1]. Competitors such as Samsung’s Galaxy S 24 Ultra weigh around 228 g, suggesting Apple’s flagship could become heavier than comparable Android flagships while offering a larger battery.

What to watch

• September launch – Apple’s official unveiling of the iPhone 18 lineup is slated for September, when final weight and thickness specs will be confirmed.
• Battery performance testing – Independent runtime benchmarks will reveal whether the extra 500 mAh translates into a noticeable endurance gain.
• Competitor response – Samsung and other Android makers may highlight thinner designs or faster‑charging solutions to counter Apple’s bulkier flagship.

The shift toward a larger battery signals Apple’s willingness to sacrifice a few grams for longer usage time, a trade‑off that could redefine user expectations for premium smartphones. Whether the added heft proves acceptable will hinge on real‑world battery performance and how rivals position their own flagship devices.