iPhone 18 battery: All you need to know

That’s quite a lot of firsts, but regardless, we are still getting a number of new iPhones this fall. 

Here’s everything we know about the larger batteries likely making it to the upcoming iPhone models. 

iPhone Ultra

Apple’s first foldable phone will most certainly make use of a dual-cell battery, with each one positioned in either half of the device. This split design would allow a larger total capacity to be used, which is something you can’t really do with a standard rigid battery.  

And the rumor mill agrees that the iPhone Ultra will easily pack the largest battery on an iPhone so far, with estimates varying between 5,400 and 5,800 mAh, which would easily place the foldable in the upper echelons of battery prowess. Sure, it’s not in silicon-carbon territory just yet, but iPhones are getting close to there, surely. 

However, Apple might have a leg up in terms of battery life thanks to its upcoming Apple A20 Pro chip, and that would make it inside the iPhone Ultra. Built on a 2nm node, it will introduce new levels of efficiency and performance, which always play a big role in  battery endurance. The Apple C2 modem will also boost the efficiency. 

iPhone 18 Pro Max

But the rumors also claim that even the physical SIM model will have a battery larger than 5,000 mAh, which is excellent news and spells one thing only: potentially excellent battery life for the iPhone 18 Pro Max. 

The difference will be in favor of the eSIM model, which will simply have more internal space for a slightly larger battery. The battery life benefit of the slightly larger battery probably wouldn’t be that major, but it’s always worth considering the model with the larger battery if one’s available in your region. As they say, there’s no replacement for displacement. 

iPhone 18 Pro

We will be getting a 4,056 mAh battery inside the iPhone 18 Pro model with a physical SIM card, whereas the US and eSIM-only variant in other regions will be equipped with a larger 4,288 mAh battery. The difference stems from the extra physical space required for the SIM slot.

Of course, the numbers are unconfirmed as of now because they’re based on leaks and rumors. 

iPhone 18

As the iPhone 18 is coming in early 2027, we don’t have any credible rumors or leaks regarding its battery size. 

As we don’t expect a major redesign or any other massive hardware change, it’s safe to assume that the device would pack a battery similar or just slightly larger than the 3,692 mAh one inside the iPhone 17. 

Probably something in the 3,750-3,800 mAh range, which wouldn’t result in a massively better battery life, but it’s still a step in the right direction.